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Reyrolle

Protection

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7SR24 Duobias

Overcurrent Relay

Answers for energy.

Summary of content (289 pages)

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Reyrolle Protection Devices 7SR24 Duobias Overcurrent Relay Answers for energy.
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7SR242 Duobias Contents Contents Technical Manual Chapters 1. Description of Operation 2. Settings, Configuration & Instruments (Appendix 1) Settings 7SR242 3. Performance Specification 4. Data Communications 5. Installation 6. Commissioning and Maintenance 7.
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7SR242 Duobias Description Of Operation 7SR242 Duobias Multi-Function 2-Winding Transformer Protection Relay Document Release History This document is issue 2010/02. The list of revisions up to and including this issue is: 2010/02 Document reformat due to rebrand 2010/02 Third issue. Software revision 2662H80001 R4c-3 2008/07 Second issue. Software revision 2662H80001R3d-2c.
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7SR242 Duobias Description Of Operation Contents Document Release History....................................................................................................................1 Software Revision History.....................................................................................................................1 Contents ..................................................................................................................................................2 List of Figures....
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7SR242 Duobias Description Of Operation 3.12 Voltage Protection: Neutral Overvoltage (59N) ......................................................................40 3.13 Voltage Protection: Under/Over Frequency (81) ....................................................................41 Section 4: Control & Logic Functions ................................................................................................42 4.1 Quick Logic .........................................................................
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SR242 Duobias Description Of Operation List of Figures Figure 1-1 Functional Diagram: 7SR242_-2_A_1-0AA0 Relay............................................................9 Figure 1-2 Functional Diagram: 7SR242_-2_A_1-0BA0 Relay..............................................................10 Figure 1-3 Functional Diagram: 7SR242_-2_A_1-0CA0 Relay .............................................................11 Figure 1-4 Connection Diagram: 7SR242 Relay.......................................................
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7SR242 Duobias Description Of Operation List of Tables Table 1-1: 7SR242 Ordering Options....................................................................................................7 Table 2-1 Summary of 7SR24 Relay Configurations .........................................................................13 Table 6-1 Operation Mode .....................................................................................................................
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7SR242 Duobias Description Of Operation Section 1: Introduction This manual is applicable to the following relays: x 7SR242 Multi-Function 2-Winding Transformer Protection Relay The 7SR242 relay integrates the protection and control elements required to provide a complete transformer protection. The ‘Ordering Options’ Tables summarise the features available in each model. General Safety Precautions ! ! Current Transformer Circuits The secondary circuit of a live CT must not be open circuited.
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7SR242 Duobias Description Of Operation Table 1-1: 7SR242 Ordering Options DUOBIAS-M Multifunctional 2 winding transformer differential protection 7 S R 2 4 2 | | | | | | | | Ź Protection Product Transformer Relay Type Differential (2 winding) | | | | 4 | | | 2 Case I/O and Fascia E8 case, 6 CT, 2 EF/REF CT, 1 VT, 9 Binary Inputs / 6 Binary Outputs, 16 LEDs E10 case, 6 CT, 2 EF/REF CT, 1 VT, 19 Binary Inputs / 14 Binary Outputs, 24 LEDs Measuring Input 1/5 A, 63.
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7SR242 Duobias Description Of Operation DUOBIAS-M (continued from previous page) 7 S R 2 4 2 Option C: - 24 - 27/59 - 59N - 81 - 37 - 46BC - 46NPS - 49 - 50 - 50G/50N - 51 - 51G/51N Standard version - plus Overfluxing Under/overvoltage Neutral voltage displacement Under/overfrequency Undercurrent Open circuit Negative phase sequence overcurrent Thermal overload Instantaneous phase fault overcurrent Instantaneous earth fault Time delayed phase fault overcurrent Time delayed earth fault Additional Functio
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7SR242 Duobias Description Of Operation 7SR242n-2aAn1-0AA0 W1-IL1 (IA) 50 BF-1 81 HBL 2 81 HBL 5 W1-IL2 (IB) 50 BF-1 81 HBL 2 81 HBL 5 W1-IL3 (IC) 50 BF-1 81 HBL 2 81 HBL 5 50 BF-1 I4 64H IG1 ICT 87HS IG2 50 BF-2 I4 87BD ICT 64H 74 CCS (x6) 74 TCS (x6) W2-IL3 (IC) W2-IL2 (IB) W2-IL1 (IA) Figure 1-1 50 BF-2 81 HBL 2 81 HBL 5 50 BF-2 81 HBL 2 81 HBL 5 50 BF-2 81 HBL 2 81 HBL 5 Functional Diagram: 7SR242_-2_A_1-0AA0 Relay ©2010 Siemens Protection Devices Limited Chapter 1
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7SR242 Duobias Description Of Operation Figure 1-2 Functional Diagram: 7SR242_-2_A_1-0BA0 Relay ©2010 Siemens Protection Devices Limited Chapter 1 Page 10 of 52
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7SR242 Duobias Description Of Operation 7SR242n-2aAn1-0CA0 W1-IL1 (IA) 37 (x2) 50 BF-1 50 (x2) 51 (x2) 49 81 HBL2 81 HBL5 W1-IL2 (IB) 37 (x2) 50 BF-1 50 (x2) 51 (x2) 49 81 HBL2 81 HBL5 W1-IL3 (IC) 37 (x2) 50 BF-1 50 (x2) 51 (x2) 49 81 HBL2 81 HBL5 50N (x2) 51N (x2) 46 BC (x2) 46 NPS (x4) 50G (x2) 51G (x4) 64H 37G (x2) IG1 50 BF-1 I4 ICT Each function element can be assigned to W1 or W2 CT inputs.
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7SR242 Duobias Description Of Operation 2 4 6 8 10 12 14 +ve -ve BI 10 7SR242 -ve 18 20 5 BO 8 BI 11 9 BI 12 BO 9 BI 13 BO 10 11 +ve 1 2 1 2 1 2 D C B A PSU CT CT/VT Data Comms (Optional) 13 +ve 15 BO 11 17 BO 12 19 +ve 27 28 27 28 27 28 27 28 Rear View Arrangement of terminals and modules 21 BI 15 -ve +ve BO 13 23 BO 14 25 27 +ve NOTES BI = BO = BI 17 24 2 Optional I/O 7 +ve BI 16 22 1 3 +ve BI 14 16 1 BO 7 Binary Input Binary Output +
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7SR242 Duobias Description Of Operation Section 2: Hardware Description 2.1 General The structure of the relay is based upon the Multi-function hardware platform. The relays are supplied in either size E8 or size E10 cases (where 1 x E = width of approx. 26mm). The hardware design provides commonality between products and components across the Multi-function range of relays.
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7SR242 Duobias Description Of Operation 2.4 Power Supply Unit (PSU) The relay PSU can be directly connected to any substation dc system rated from 30V dc to 220V dc. In the event of the station battery voltage level falling below the relay minimum operate level the PSU will automatically switch itself off and latch out – this prevents any PSU overload conditions occurring. The PSU is reset by switching the auxiliary supply off then on. 2.
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7SR242 Duobias Description Of Operation Liquid Crystal Display (LCD) A 4 line by 20-character liquid crystal display indicates settings, instrumentation, fault data and control commands. To conserve power the display backlighting is extinguished when no buttons are pressed for a user defined period. A setting within the “SYSTEM CONFIG” menu allows the timeout to be adjusted from 1 to 60 minutes and “Off” (backlight permanently on). After an hour the display is completely de-activated.
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7SR242 Duobias Description Of Operation initiates operation. The LED illumination colour is assigned in the OUTPUT CONFIG>LED CONFIG menu for both Pickup and Operate initiation. Functions are assigned to the LEDs in the OUTPUT CONFIG>OUTPUT MATRIX menu. Each LED can be labelled by withdrawing the relay and inserting a label strip into the pocket behind the front fascia. A ‘template’ is available to allow users to create and print customised legends.
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7SR242 Duobias Description Of Operation 2.8 Binary inputs The binary inputs are opto-couplers operated from a suitably rated dc supply. Relays are fitted with 9 or 19 binary inputs (BI). The user can assign any binary input to any of the available functions (INPUT CONFIG > INPUT MATRIX). The Power Supply module includes the relay basic I/O. The module includes 3 x BI. Pick-up (PU) and drop-off (DO) time delays are associated with each binary input.
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7SR242 Duobias Description Of Operation 2.9 Binary outputs (Output Relays) Relays are fitted with 6 or 14 binary outputs. All outputs are fully user configurable and can be programmed to operate from any or all of the available functions. The Power Supply module includes the relay basic I/O. The module includes six binary outputs each fitted with 1 contact – providing in total 1 x normally closed (NC), 2 x change-over (CO) and 3 x normally open (NO) contacts.
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7SR242 Duobias Description Of Operation Logic signals, e.g. '51-1' Reset LEDs & Outputs (TEST/RESET key, Binary Input, Data Comms) BO 1 S R Hand Reset Output 1 Q Event & & BO 1 hand reset 1 Min Operate Time OUTPUT CONFIG> OUTPUT MATRIX & 1 (Or gates) OUTPUT CONFIG> BINARY OUTPUT CONFIG OUTPUT CONFIG> BINARY OUTPUT CONFIG BO n Output n S R 1 1 Figure 2-3 Event & & BO n hand reset Q & Binary Output Logic 2.
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7SR242 Duobias Description Of Operation Section 3: Protection Functions 3.1 Current Protection: Differential Protection Comprises both biased differential and high-set differential elements. The fundamental frequency current is measured with the line CT inputs. These line currents are both multiplied and vector corrected before being applied to the current differential elements. 3.1.1 ICT The Wn ICT Multiplier setting is applied to the line currents – the CT secondary currents.
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7SR242 Duobias Description Of Operation 3.1.2 Overall Biased Differential (87BD) IW1 IW2 IW1 IW2 2nd Bias Slope Type st D1 87B 87BD Initial Setting S Bias lope Bias (Restraint) Current IW1 IW2 2 1st Bias Slope Limit Figure 3-1 Biased Differential Characteristic Figure 3.1-1 illustrates the biased differential characteristic. Within the relay the fundamental frequency RMS line currents are modified by the ICT Multiplier and ICT Connection settings (see 3.1.
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7SR242 Duobias Description Of Operation 87BD Element 87BD Initial Disabled 87BD 1st Bias Slope Enabled 87BD 1st Bias Slope Limit 87BD 2nd Bias Slope Type & 87BD 2nd Bias Slope Inhibit 87BD c 87BD ‘A’ Inhibit c ICT A W1 ICT Multiplier Pickup 1 trip W1 ICT Connection 87BD ‘B’ Inhibit c W1-IL1 B W1-IL2 Pickup trip W1-IL3 87BD ‘C’ Inhibit c C 87BD Delay Pickup 87BD 1 trip ICT General Pickup W2 ICT Multiplier W2 ICT Connection W2-IL1 W2-IL2 W2-IL3 87BD Inrush Action 81HBL2 Ele
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7SR242 Duobias Description Of Operation 3.1.3 87HS IW1 IW2 IW1 IW2 2 Figure 3-3 Differential Highset Characteristic Figure 3.1-3 illustrates the differential highset characteristic. Within the relay the fundamental frequency RMS line currents are modified by the ICT Multiplier and ICT Connection settings (see 3.1.1) before being applied to the differential highset elements.
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7SR242 Duobias Description Of Operation 87HS Element Disabled Enabled & 87HS Setting Inhibit 87HS c 87HS ‘A’ c Inhibit ICT Pickup trip W1 ICT Multiplier 87HS ‘B’ c Inhibit W1 ICT Connection W1-IL1 & Pickup trip W1-IL2 W1-IL3 General Pickup 87HS ‘C’ c Inhibit 87HS Delay Pickup & 87HS trip ICT W2 ICT Multiplier W2 ICT Connection W2-IL1 W2-IL2 W2-IL3 87HS Inrush Action 81HBL2 Element 81HBL2 Setting Disabled 81HBL2 Bias Enabled c > > > Wn-IL1 Wn-IL2 Wn-IL3 81HBL5 Setting Disabled
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7SR242 Duobias Description Of Operation 3.2 Current Protection: Phase Overcurrent (51, 50) The optional phase overcurrent elements have a common setting to measure either fundamental frequency RMS or True RMS current: True RMS current: 51/50 Measurement = RMS Fundamental Frequency RMS current: 51/50 Measurement = Fundamental 3.2.1 Instantaneous Overcurrent Protection (50) Optionally two instantaneous overcurrent elements are provided, each can be selected to either winding 1 or winding 2.
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7SR242 Duobias Description Of Operation 3.2.2 Time Delayed Overcurrent Protection (51) Optionally two time delayed overcurrent elements are provided, each can be selected to either winding 1 or winding 2. 51-n Setting sets the pick-up current level. A number of shaped characteristics are provided. An inverse definite minimum time (IDMT) characteristic is selected from IEC, ANSI or user defined curves using 51-n Char.
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7SR242 Duobias Description Of Operation 3.3 Current Protection: Derived Earth Fault (50N, 51N) The earth current is derived by calculating the sum of the measured line currents. These optional elements utilise RMS current values of the fundamental frequency (50 or 60Hz). 3.3.1 Instantaneous Derived Earth Fault Protection (50N) Optionally two instantaneous derived earth fault elements are provided, each can be selected to either winding 1 or winding 2.
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7SR242 Duobias Description Of Operation 3.3.2 Time Delayed Derived Earth Fault Protection (51N) Optionally two time delayed derived earth fault elements are provided, each can be selected to either winding 1 or winding 2. 51N-n Setting sets the pick-up current level. A number of shaped characteristics are provided. An inverse definite minimum time (IDMT) characteristic is selected from IEC, ANSI or user defined curves using 51N-n Char.
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7SR242 Duobias Description Of Operation 3.4 Current Protection: Measured Earth Fault (50G, 51G) The earth current is measured directly via dedicated current analogue inputs. These optional elements utilise either RMS or Fundamental current values as defined by the 51G/50G Measurement setting (MEASURED E/F menu). 3.4.1 Instantaneous Measured Earth Fault Protection (50G) Optionally two instantaneous measured earth fault elements are provided, each can be selected to either winding 1 or winding 2.
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7SR242 Duobias Description Of Operation 3.4.2 Time Delayed Measured Earth Fault Protection (51G) Optionally two time delayed measured earth fault elements are provided, each can be selected to either winding 1 or winding 2. 51G-n Setting sets the pick-up current level. A number of shaped characteristics are provided. An inverse definite minimum time (IDMT) characteristic is selected from IEC, ANSI or user defined curves using 51G-n Char.
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7SR242 Duobias Description Of Operation 3.5 Current Protection: High Impedance Restricted Earth Fault (64H) Two high impedance restricted earth fault elements are provided, one for each transformer winding The relay utilises fundamental current measurement values for this function. The single phase current input is derived from the residual output of line/neutral CTs connected in parallel.
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7SR242 Duobias Description Of Operation 3.6 Open Circuit (46BC) Optionally two open circuit elements are provided, each can be selected to either winding 1 or winding 2. The element calculates the ratio of NPS to PPS currents. Where the NPS:PPS current ratio is above 46BC Setting an output is given after the 46BC Delay. The Open Circuit function can be inhibited from Inhibit 46BC A binary or virtual input . Gn 46BC-n U/I Guarded Operation of the undercurrent guard function.
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7SR242 Duobias Description Of Operation 3.7 Current Protection: Negative Phase Sequence Overcurrent (46NPS) Optionally four NPS current elements are provided – 2 x 46IT and 2 x 46DT. Each element can be selected to either winding 1 or winding 2. The 46IT elements can be configured to be either definite time lag (DTL) or inverse definite minimum time (IDMT), 46IT Setting sets the pick-up current level for the element. A number of shaped characteristics are provided.
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7SR242 Duobias Description Of Operation 3.8 Current Protection: Under-Current (37, 37G) Optionally two under-current elements are provided for both line and measured earth current, each can be selected to either winding 1 or winding 2. Each phase has an independent level detector and current-timing element. 37-n Setting sets the pick-up current. An output is given after elapse of the 37-n Delay setting.
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7SR242 Duobias Description Of Operation 3.9 Current Protection: Thermal Overload (49) Optionally a phase segregated thermal overload element is provided, this can be selected to either winding 1 or winding 2. The thermal state is calculated using the measured True RMS current. Should the current rise above the 49 Overload Setting for a defined time an output signal will be initiated.
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7SR242 Duobias Description Of Operation 49 Thermal Overload Disabled 49 Overload Setting 49 Time Constant 49 Capacity Alarm Enabled & c Inhibit 49 cap alarm Wn-IL1 trip 1 49 Alarm 1 49 Trip cap alarm Wn-IL2 trip cap alarm Wn-IL3 Figure 3-15 trip Logic Diagram: Thermal Overload Protection (49) ©2010 Siemens Protection Devices Limited Chapter 1 Page 36 of 52
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7SR242 Duobias Description Of Operation 3.10 Voltage Protection: Over Fluxing (24) Optionally, three over fluxing elements are provided – 2 x 24DT and 1 x 24IT Char elements. The 24DT Elements have a DTL characteristic. 24DT Setting sets the pick-up level and 24DT Delay the follower time delay. An output is given if the Volts/Hertz ratio is above setting for the duration of the delay. The 24DT-n Hysteresis setting allows the user to vary the pick-up/drop-off ratio for the element.
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7SR242 Duobias Description Of Operation Figure 3-17 Logic Diagram: Overfluxing Elements (24) ©2010 Siemens Protection Devices Limited Chapter 1 Page 38 of 52
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7SR242 Duobias Description Of Operation 3.11 Voltage Protection: Under/Over Voltage (27/59) Optionally four under/over voltage elements are provided. The relay utilises fundamental voltage measurement values for this function. 27/59-n Setting sets the pick-up voltage level for the element. The sense of the element (undervoltage or overvoltage) is set by the 27/59-n Operation setting. Voltage elements are blocked if the measured voltage falls below the 27/59 U/V Guard setting.
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7SR242 Duobias Description Of Operation 3.12 Voltage Protection: Neutral Overvoltage (59N) Optionally two Neutral Overvoltage (or Neutral Voltage Displacement) elements are provided. One of the elements can be configured to be either definite time lag (DTL) or inverse definite minimum time (IDMT), 59NIT Setting sets the pick-up voltage level (3V0) for the element. An inverse definite minimum time (IDMT) can be selected using 59NIT Char.
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7SR242 Duobias Description Of Operation 3.13 Voltage Protection: Under/Over Frequency (81) Optionally six under/over frequency elements are provided. Frequency elements are blocked if the measured voltage falls below the 81 U/V Guard setting. The sense of the element (under-frequency or over-frequency) is set by the 81-n Operation setting. 81-n Setting sets the pick-up frequency for the element. An output is given after elapse of the 81-n Delay setting.
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7SR242 Duobias Description Of Operation Section 4: Control & Logic Functions 4.1 Quick Logic The ‘Quick Logic’ feature allows the user to input up to 16 logic equations (E1 to E16) in text format. Equations can be entered using Reydisp or at the relay fascia. Each logic equation is built up from text representing control characters. Each can be up to 20 characters long. Allowable characters are: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 Digit ( ) Parenthesis ! ‘NOT’ Function .
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P. U .D EL A Figure 4-1 AY EL .D .O D Y 7SR242 Duobias Description Of Operation Sequence Diagram showing PU/DO Timers in Quick Logic (Counter Reset Mode Off) When the count value = En Counter Target the output of the counter (En) = 1 and this value is held until the initiating conditions are removed when En is instantaneously reset. The output of En is assigned in the OUTPUT CONFIG>OUTPUT MATRIX menu where it can be programmed to any binary output (O), LED (L) or Virtual Input/Output (V) combination.
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7SR242 Duobias Description Of Operation Section 5: Supervision Functions 5.1 Circuit Breaker Failure (50BF) Two CB Fail elements are provided – one element per winding. Each circuit breaker fail function has two time delayed outputs that can be used for combinations of re-tripping or back-tripping. CB Fail outputs are given after elapse of the 50BF-n-1 Delay or 50BF-n-2 Delay settings. The two timers run concurrently.
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7SR242 Duobias Description Of Operation 5.2 Trip/Close Circuit Supervision (74TCS/74CCS) The relay provides six trip and six close circuit supervision elements, all elements are identical in operation and independent from each other allowing 6 trip and 6 close circuits to be monitored. One or more binary inputs can be mapped to 74TCS-n/74CCS-n. The inputs are connected into the trip circuit such that at least one input is energised when the trip circuit wiring is intact.
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7SR242 Duobias Description Of Operation 5.3 Inrush Detector (81HBL2) Inrush detector elements monitor the line currents. The inrush detector can be used to block the operation of selected elements during transformer magnetising inrush conditions. The 81HBL2 Bias setting allows the user to select between Phase, Sum and Cross methods of measurement: Phase Each phase is inhibited separately.
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7SR242 Duobias Description Of Operation 5.5 Demand Maximum, minimum and mean values of line currents and voltage (where applicable) are available as instruments which can be read in the relay INSTRUMENTS MENU or via Reydisp. The DATA STORAGE > DEMAND DATA LOG > Data Log Period setting is used to define the time/duration after which the instrument is updated. The updated value indicates the maximum, minimum and mean values for the defined period.
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7SR242 Duobias Description Of Operation Section 6: Other Features 6.1 Data Communications Two communication ports, COM1 and COM2 are provided. RS485 connections are available on the terminal blocks at the rear of the relay (COM1). A USB port, COM 2, is provided at the front of the relay for local access using a PC. Optionally, two additional fibre optic communication ports with ST connectors can be provided at the rear of the relay - COM3 and COM4.
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7SR242 Duobias Description Of Operation 2 I t CB2 Wear: As CB1 The status of each counter can be viewed in the INSTRUMENTS mode. Binary outputs can be mapped to each of the above counters, these outputs are energised when the user defined Alarm Limit is reached. 6.3 Data Storage 6.3.1 General The relay stores three types of data: relay event records, analogue/digital waveform records and fault records.
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7SR242 Duobias Description Of Operation Waveforms are sampled at a rate of 1600Hz. Stored waveforms can be erased using the DATA STORAGE>Clear Waveforms setting. 6.3.4 Fault Records Up to ten fault records can be stored and displayed on the Fascia LCD. Fault records provide a summary of the relay status at the time of trip, i.e. the element that issued the trip, any elements that were picked up, the fault type, LED indications, date and time. The Max Fault Rec.
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7SR242 Duobias Description Of Operation 6.5 Operating Mode The relay has three operating modes, Local, Remote and Out of Service. functions operation in each mode.
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7SR242 Duobias Description Of Operation 6.7.1 Time Synchronisation – Data Comms Where the data comms channel(s) is connected to a dedicated substation automation system the relay can be time synchronised using the relevant command within IEC 60870-5-103 or optional DNP3.0 protocols. The time can also be synchronised from ‘Reydisp Evolution’ which utilises the communications support software. 6.7.2 Time Synchronisation – Binary Input A binary input can be mapped Clock Sync from BI.
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7SR242 Duobias Settings, Configuration & Instruments Guide 7SR242 Duobias Multi-Function 2-Winding Transformer Protection Relay Document Release History This document is issue 2010/02. The list of revisions up to and including this issue is: 2010/02 Document reformat due to rebrand 2010/02 Third issue. Software revision 2662H80001 R4c-3 2008/07 Second issue. Software revision 2662H80001R3d-2c.
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7SR242 Duobias Settings, Configuration & Instruments Guide Contents Document Release History....................................................................................................................1 Software Revision History.....................................................................................................................1 Contents ..................................................................................................................................................
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7SR242 Duobias Settings, Configuration & Instruments Guide List of Figures Figure -1-1: Menu.....................................................................................................................................4 Figure -1-2 Fascia Contrast symbol .........................................................................................................4 Figure 1-3 Facia of 7SR242 Relay ...........................................................................................................
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7SR242 Duobias Settings, Configuration & Instruments Guide Section 1: Introduction 1.1 Relay Menus And Display All relay fascias contain the same access keys although the fascias may differ in appearance from model to model. The basic menu structure is also the same in all products and consists of four main menus, these being, Settings Mode - allows the user to view and (if allowed via the settings mode password) change settings in the relay. Instruments Mode - allows the user to view the relay meters e.
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7SR242 Duobias Settings, Configuration & Instruments Guide Figure 1-3 Facia of 7SR242 Relay ©2010 Siemens Protection Devices Limited Chapter 2 Page 5 of 20
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7SR242 Duobias Settings, Configuration & Instruments Guide 1.2 Operation Guide 1.2.1User Interface Operation The basic menu structure flow diagram is shown in Figure 1.2-2. This diagram shows the main modes of display: Settings Mode, Instrument Mode, Fault Data Mode and Control Mode. When the relay leaves the factory all data storage areas are cleared and the settings set to default as specified in settings document.
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7SR242 Duobias Settings, Configuration & Instruments Guide 7SR242 DUOBIAS __________________________ ENTER to CONTROL INSTRUMENTS MODE SETTINGS DISPLAY MODE INSTRUMENTS MODE CB1 SYSTEM CONFIGURATION FAVOURITE METERS CB2 CT/VT CONFIGURATION DIFFERENTIAL METERS E/F Protection FUNCTION CONFIG CURRENT METERS Set L or R DIFFERENTIAL PROTECTION VOLTAGE METERS Set Remote CURRENT PROTECTION Set Local 51-1 51-2 50-1 50-2 FREQUENCY METERS 51N-1 51N-2 50N-2 50N-1 OVERFLUXING METERS 51G-1 51G-2
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7SR242 Duobias Settings, Configuration & Instruments Guide 1.3 Settings Display The Settings Mode is reached by pressing the READ DOWN button from the relay identifier screen. Once the Settings Mode title screen has been located pressing the READ DOWN button takes the user into the Settings mode sub-menus. Each sub-menu contains the programmable settings of the relay in separate logical groups. The sub menus are accessed by pressing the TEST/RESET button.
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7SR242 Duobias Settings, Configuration & Instruments Guide DIFFERENTIAL METERS This is the sub-group that includes all the meters that are associated with Current TEST/RESET allows access to this sub-group to view W1 Line Ia Ib Ic W2 Line Ia Ib Ic W1 Relay Ia Ib Ic W2 Relay Ia Ib Ic Operate Ia Ib Ic Restrain Ia Ib Ic W1 1st Harmonic Ia Ib Ic W1 2nd Harmonic Ia Ib Ic nd W1 5 Harmonic Ia Ib Ic W2 1st Harmonic nd W2 2 0.00xIn ----o 0.00xIn ----o 0.00xIn ----o 0.00xIn ----o 0.00xIn ----o o 0.
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7SR242 Duobias Settings, Configuration & Instruments Guide CURRENT METERS This is the sub-group that includes all the meters that are associated with Current TEST/RESET allows access to this sub-group to view W1 Primary Ia Ib Ic W1 Secondary Ia Ib Ic W1 Nominal Ia Ib Ic W1 Sequence Izps Ipps Inps W1 Derived Earth (In) Ia Ib Ic W2 Primary 0.00kA 0.00kA 0.00kA 0.00A 0.00A 0.00A 0.00xIn ----o 0.00xIn ----o 0.00xIn ----o 0.00xIn ----o o 0.00xIn ---0.
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7SR242 Duobias Settings, Configuration & Instruments Guide VOLTAGE METERS This is the sub-group that includes all the meters that are associated with Voltage TEST/RESET allows access to this sub-group to view Voltage Meters Pri (Ph-Ph) Sec Nom 0.00kV 0.00V 0.00xVn FREQUENCY METERS This is the sub-group that includes all the meters that are associated with Frequency TEST/RESET allows access to this sub-group to view Frequency 00.
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7SR242 Duobias Settings, Configuration & Instruments Guide W1 Ia Line W1 Ia prim W1 Ia secy W1 Ia Nom. W1 1st Harm W1 2nd Harm W1 W1 5th Therm Harm W1 Ib Line W1 Ib prim W1 Ib secy W1 Ib Nom. W1 1st Harm W1 2nd Harm W1 W1 5th Therm Harm W1 Ic Line W1 Ic prim W1 Ic secy W1 Ic Nom. W1 1st Harm W1 2nd Harm W1 W1 5th Therm Harm W1 I Seq. W1 I EF Der. Meas Earth 1 ICT W1 Rel. Ia W1 Rel. Ib W1 Rel. Ic Ia Op. 7SR242_-2_A_1-0CA0 Ia Rest. Ib Op. Ib Rest. Ic Op. Ic Rest. W2 Rel.
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7SR242 Duobias Settings, Configuration & Instruments Guide MAINTENANCE METERS This is the sub-group that includes all the meters that are associated with Maintenance TEST/RESET allows access to this sub-group to view CB1 Manual Close Last Close CB1 Manual Open Last Open CB2 Manual Close Last Close CB2 Manual Open Last Open CB1 Total Trips Count Target CB1 Delta Trips Count Target CB2 Total Trips Count Target CB2 Delta Trips Count Target CB1 Wear Phase A Phase B Phase C CB2 Wear Phase A Phase B Phase C
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7SR242 Duobias Settings, Configuration & Instruments Guide GENERAL ALARM METERS This is the sub-group that includes all the meters that are associated with the Binary inputs TEST/RESET allows access to this sub-group to view General Alarms ALARM 1 General Alarms ALARM 2 General Alarms ALARM 3 General Alarms ALARM 4 General Alarms ALARM 5 General Alarms ALARM 6 General Alarms ALARM 7 General Alarms ALARM 8 General Alarms ALARM 9 General Alarms ALARM 10 General Alarms ALARM 11 General Alarms ALARM 12 Cl
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7SR242 Duobias Settings, Configuration & Instruments Guide BINARY OUTPUT METERS This is the sub-group that includes all the meters that are associated with the Binary Outputs TEST/RESET allows access to this sub-group to view BO 1-8 BO 9-14 ---- ------- -- Displays the state of DC binary Outputs 1 to 8.
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7SR242 Duobias Settings, Configuration & Instruments Guide QUICK LOGIC METERS to view E 1-8 E 9-16 E1 Equation EQN TMR 0-0 CNT 0-1 En Equation 1.5 0 =0 =0 =0 Fault Data Mode The Fault Data Mode sub menu lists the time and date of the previous ten protection operations. The stored data about each fault can be viewed by pressing the TEST/RESET button. Each record contains data on the operated elements, analogue values and LED flag states at the time of the fault.
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7SR242 Duobias Settings, Configuration & Instruments Guide Section 2: Setting the Relay Using Reydisp Evolution To set the relay using the communication port the user will need the following:PC with REYDISP Evolution Installed. (REYDISP can be downloaded from our website www.siemens.com/energy and found under the submenu ‘Software’)This software requires windows 2000-service pack 4 or above, or windows XP with service pack 2 or above. 2.
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7SR242 Duobias Settings, Configuration & Instruments Guide 2.1.2 Rear RS485 connection Figure 2-2 RS485 connection to PC 2.1.3 Optional rear fibre optic connection Figure 2-3 Fibre Optic Connection to PC Sigma devices have a 25 pin female D connector with the following pin out.
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7SR242 Duobias Settings, Configuration & Instruments Guide 2.1.4 Configuring Relay Data Communication Using the keys on the relay fascia scroll down the settings menu’s into the ‘communications’ menu. All of the below settings may not be available in all relay types. Reydisp software is compatible with IEC60870-5-103 protocol.
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7SR242 Duobias Settings, Configuration & Instruments Guide 2.1.5 Connecting to the Relay via Reydisp When Reydisp software is running all available communication ports of the PC will automatically be detected. On the start page tool bar open up the sub-menu File > Connect. The ‘Communication Manager’ window will display all available communication ports.
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7SR242 Duobias Performance Specification 7SR242 Duobias Multi-Function 2-Winding Transformer Protection Relay Document Release History This document is issue 2010/02. The list of revisions up to and including this issue is: 2010/02 Document reformat due to rebrand 2010/02 Third issue. Software revision 2662H80001 R4c-3 2008/07 Second issue. Software revision 2662H80001R3d-2c.
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7SR242 Duobias Performance Specification Contents Document Release History....................................................................................................................1 Software Revision History.....................................................................................................................1 Contents ..................................................................................................................................................
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7SR242 Duobias Performance Specification 2.4.5 Operate and Reset Level (46IT) ................................................................................19 2.4.6 Operate and Reset Time (46IT) .................................................................................20 2.5 49 Thermal Overload ..............................................................................................................21 2.5.1 Reference..............................................................................
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7SR242 Duobias Performance Specification 3.2 74TCS/CCS Trip/Close Circuit Supervision............................................................................43 3.2.1 Reference...................................................................................................................43 3.2.2 Operate and Reset Time............................................................................................43 3.3 81HBL2 Inrush Detector ................................................................
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7SR242 Duobias Performance Specification Section 1: Common Functions 1.1 General 1.1.1 CE Conformity This product is CE compliant to relevant EU directives. 1.1.2 Reference This product complies with IEC 60255-3, IEC 60255-6 and IEC 60255-12. 1.1.2.1 Accuracy Reference Conditions This product has been tested under the following conditions, unless specifically stated otherwise.
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7SR242 Duobias Performance Specification 1.2 Energising Quantities 1.2.1 Auxiliary Power Supply Nominal VAUX 30, 48, 110, 220 VDC 1.2.1.1 Attribute Operating Range 24 to 290 VDC Burden Value 30V DC 48V DC 110V DC 220V DC Quiescent (typical) 6.0 W Quiescent (back light) 7.0 W Quiescent (typical) 5.5W Quiescent (back light) 6.5W Quiescent (typical) 6.5W Quiescent (back light) 7.5W Quiescent (typical) 7.5W Quiescent (back light) 8.5W 1.2.
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7SR242 Duobias Performance Specification 1.2.3 AC Voltage Nominal Operating Range Vn 40 to 160 V Up to 270 V fn 50, 60Hz 47 to 62Hz 1.2.3.1 Attribute Burden Value AC Burden 0.01 VA at 110 V 1.2.4 Binary (Digital) Outputs Contact rating to IEC 60255-0-2 Attribute Value Carry continuously Make and carry (L/R d 40 ms and V d 300 V) Break ( d 5 A and d 300 V) 5A AC or DC for 0.5 s 20A AC or DC for 0.2 s 30A AC or DC AC resistive 1250 VA AC inductive 250 VA at p.f. d 0.
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7SR242 Duobias Performance Specification 1.2.5 Binary (Digital) Inputs Nominal VBI 1.2.5.1 Attribute Operating Range 19 VDC 17 to 290 VDC 88 VDC 74 to 290 VDC Performance Maximum DC current for operation Value VBI = 19 V 1.5mA VBI = 88 V 1.5mA Reset/Operate voltage ratio t 90 % Response time < 7ms Response time when programmed to energise an output relay contact (i.e.
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7SR242 Duobias Performance Specification ESI-1 + 470 + ESI-2 30V DC Nominal (24 – 37.5V Operative) IOP > 10mA 220 30V DC Nominal (24 – 37.5V Operative) IOP > 20mA BI (19V) 1K5 BI (19V) 820 - + 1K6 - + 48V DC Nominal (37.5 – 60V Operative) IOP > 10mA 820 48V DC Nominal (37.5 – 60V Operative) IOP > 20mA BI (19V) BI (19V) 820 1K5 - - BI DTL = 10ms (10μF, 60V Capacitance discharge) + 2K0 110V DC Nominal (87.5 – 137.5V Operative) IOP > 25mA + 110V DC Nominal (87.5 – 137.
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7SR242 Duobias Performance Specification 1.3 Functional Performance 1.3.1 Instrumentation Instrument Value Reference Typical accuracy I Current I t 0.1 xIn r 1 % In V Voltage V t 0.8 xVn r 1 % Vn 1.3.2 USB Data Communication Interface Attribute Value Physical layer Electrical Connectors USB-Type B 1.3.3 Fibre optic Data Communication Interface Attribute Value Physical layer Fibre-optic Connectors ST Recommended fibre 62.
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7SR242 Duobias Performance Specification 1.4 Environmental Performance 1.4.1 General 1.4.1.1 Temperature IEC 60068-2-1/2 Type Level Operating range -10 qC to +55 qC Storage range -25 qC to +70 qC 1.4.1.2 Humidity IEC 60068-2-3 Type Operational test 1.4.1.3 Level Between all terminals and earth, or between any two independent circuits 5.0 kV, 1.2/50 Ps 0.5j Insulation IEC 60255-5 Type Level Between any terminal and earth Between independent circuits Across normally open contacts 1.4.1.
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7SR242 Duobias Performance Specification 1.4.3 Immunity 1.4.3.1 Auxiliary DC Supply Variation Quantity Value Allowable superimposed ac component d 12% of DC voltage Allowable breaks/dips in supply (collapse to zero from nominal voltage) d 20ms 1.4.3.2 High Frequency Disturbance IEC 60255-22-1 Class III Type Level Common (longitudinal) mode 2.5 kV Series (transverse) mode 1.0 kV 1.4.3.3 Contact discharge 80 MHz to 1000 MHz Variation 8.
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7SR242 Duobias Performance Specification 1.4.4 Mechanical 1.4.4.1 Vibration (Sinusoidal) IEC 60255-21-1 Class I Type Level Vibration response 0.5 gn Vibration endurance 1.0 gn 1.4.4.2 Variation d5% Shock and Bump IEC 60255-21-2 Class I Type Level Variation Shock response 5 gn, Shock withstand 15 gn, 11 ms Bump test 10 gn, 16 ms 1.4.4.3 d5% Seismic IEC 60255-21-3 Class I Type Seismic response 1.4.4.
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7SR242 Duobias Performance Specification Section 2: Protection Functions 2.1 24 Over Fluxing 2.1.1 Reference (24DT) Parameter Value V/fs Setting 0.10, 0.11… 2.0 x Nominal Voltage / Nominal Frequency Hyst Hysteresis setting 0, 0.1… 80.0% td Delay setting 0.00, 0.01…20.00, 20.50… 100, 101… 1000, 1010… 10000, 10100… 14400 s 2.1.2 Operate and Reset Level (24DT) V/fop Attribute Value Operate level 100% x V/fs, r 2 % or r 0.
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7SR242 Duobias Performance Specification 2.1.
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7SR242 Duobias Performance Specification 27/59 Under/Over Voltage 2.1.7 Reference Parameter Value Vs Setting 5, 5.5…200V hyst Hysteresis setting 0, 0.1… 80.0% td Delay setting 0.00, 0.01…20.00, 20.50… 100, 101… 1000, 1010… 10000, 10100… 14400 s 2.1.8 Operate and Reset Level Vop Attribute Value Operate level 100 % Vs, r 1 % or r0.
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7SR242 Duobias Performance Specification 2.2 37,37G Undercurrent 2.2.1 Reference Parameter Value Is 37-n Setting 0.05, 0.10…5.0 xIn td 37-n Delay setting 0.00, 0.01…20.00, 20.50… 100, 101… 1000, 1010… 10000, 10100… 14400 s Is 37-n U/I Guard Setting 0.05, 0.10…5.0 xIn Parameter Value Is 37G-n Setting 0.05, 0.10…5.0 xIn td 37G-n Delay setting 0.00, 0.01…20.00, 20.50… 100, 101… 1000, 1010… 10000, 10100… 14400 s 2.2.
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7SR242 Duobias Performance Specification 2.3 46BC Open Circuit 2.3.1 Reference Parameter Value Iset NPS to PPS ratio 20,21…100% tf Delay setting 0.03,04,20.0,20.1,100,101,1000,1010…..14400 s Is 46BC-n U/I Guard Setting 0.05, 0.10…5.0 xIn 2.3.
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7SR242 Duobias Performance Specification 2.4 46NPS Negative Phase Sequence Overcurrent 2.4.1 Reference (46DT) Parameter Value Is Setting 0.05, 0.06... 4.0xIn td Delay setting 0.00, 0.01…20.00, 20.50… 100, 101… 1000, 1010… 10000, 10100… 14400 s 2.4.
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7SR242 Duobias Performance Specification 2.4.6 Operate and Reset Time (46IT) Attribute Value Starter operate time (t 2xIs) 35 ms, r 10ms t op char = IEC-NI, IEC-VI, IEC-EI, IEC-LTI top char = DTL t op ANSI DECAYING ª « « ¬ u Tm , r 5 % absolute or r 50 ms, IEC-NI : IEC-VI : IEC-EI : IEC-LTI : A >IsI @P K = 0.14, D = 0.02 K = 13.5, D = 1.0 K = 80.0, D = 2.0 K = 120.0, D = 1.0 º B » u Tm , r 5 % absolute or r 50 ms, » 1 ¼ for char = ANSI-MI : A = 0.0515, B = 0.114, P = 0.
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7SR242 Duobias Performance Specification 2.5 49 Thermal Overload 2.5.1 Reference Parameter Value Is Overload setting 0.10, 0.11… 3 xIn W Time constant setting 1, 1.5… 1000 min 2.5.2 Operate and Reset Level Iol Attribute Value Overload level 100 % Is, r 5 % or r 1% In Reset level t 95 % Iol Repeatability r1% Variation -10 °C to +55 °C d5% fnom - 3 Hz to fnom + 2 Hz d5% 2.5.
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7SR242 Duobias Performance Specification 100000 10000 W = 1000 mins 1000 Time (sec) W = 100 mins 100 W = 10 mins 10 W = 1 min 1 0.
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7SR242 Duobias Performance Specification 2.6 50 instantaneous overcurrent 2.6.1 Reference Parameter Is td Value Setting 0.05, 0.10… 25, 25.5… 50 xIn Delay setting 0.00, 0.01…20.00, 20.50… 100, 101… 1000, 1010… 10000, 10100… 14400 s 2.6.2 Operate and Reset Level Iop Attribute Value Operate level 100 % Is, r 5 % or r 1% In Reset level t 95 % Iop Repeatability r1% Transient overreach (X/R d 100) d -5 % Variation -10 °C to +55 °C d5% fnom - 3 Hz to fnom + 2 Hz d5% 2.6.
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7SR242 Duobias Performance Specification 2.7 50N instantaneous Derived Earth Fault 2.7.1 Reference Parameter Is td Value Setting 0.05, 0.10… 25, 25.5… 50 xIn Delay setting 0.00, 0.01…20.00, 20.50… 100, 101… 1000, 1010… 10000, 10100… 14400 s 2.7.2 Operate and Reset Level Iop Attribute Value Operate level 100 % Is, r 5 % or r 1% In Reset level t 95 % Iop Repeatability r1% Transient overreach (X/R d 100) d -5 % Variation -10 °C to +55 °C d5% fnom - 3 Hz to fnom + 2 Hz d5% 2.7.
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7SR242 Duobias Performance Specification 2.8 50G Instantaneous Measured Earth Fault 2.8.1 Reference Parameter Value Is Setting 0.005…25.0 xIn td Delay setting 0.00, 0.01…20.00, 20.50… 100, 101… 1000, 1010… 10000, 10100… 14400 s 2.8.2 Operate and Reset Level Iop Attribute Value Operate level 100 % Is, r 5 % or r 1% In Reset level t 95 % Iop Repeatability r1% Transient overreach (X/R d 100) d -5 % Variation -10 °C to +55 °C d5% fnom - 3 Hz to fnom + 2 Hz d5% 2.8.
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7SR242 Duobias Performance Specification 2.9 51 Time Delayed Overcurrent 2.9.1 Reference Parameter Value Is Setting 0.05, 0.1… 2.5 xIn char Characteristic setting IEC-NI, -VI, -EI, -LTI; ANSI-MI, -VI, -EI; DTL Tm Time Multiplier setting 0.025, 0.05… 1.6 td Delay setting 0, 0.01… 20 s tres Reset setting ANSI DECAYING, 0, 1… 60 s 2.9.
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7SR242 Duobias Performance Specification 2.9.3 Operate and Reset Time Attribute Value Starter operate time (t 2xIs) 20 ms, r 20ms t op char = IEC-NI, IEC-VI, IEC-EI, IEC-LTI top char = DTL t op ANSI DECAYING ª « « ¬ u Tm , r 5 % absolute or r 30 ms, IEC-NI : IEC-VI : IEC-EI : IEC-LTI : A >IsI @P K = 0.14, D = 0.02 K = 13.5, D = 1.0 K = 80.0, D = 2.0 K = 120.0, D = 1.0 º B » u Tm , r 5 % absolute or r 30 ms, » 1 ¼ for char = ANSI-MI : A = 0.0515, B = 0.114, P = 0.02 ANSI-VI : A = 19.
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7SR242 Duobias Performance Specification 2.10 51N Time Delayed Derived Earth Fault 2.10.1 Reference Parameter Value Is Setting 0.05, 0.1… 2.5 xIn char Characteristic setting IEC-NI, -VI, -EI, -LTI; ANSI-MI, -VI, -EI; DTL Tm Time Multiplier setting 0.025, 0.05… 1.6 td Delay setting 0, 0.01… 20 s tres Reset setting ANSI DECAYING, 0, 1… 60 s 2.10.
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7SR242 Duobias Performance Specification 2.10.3 Operate and Reset Time Attribute Value Starter operate time (t 2xIs) 20 ms, r 20ms t op char = IEC-NI, IEC-VI, IEC-EI, IEC-LTI top char = DTL t op ANSI DECAYING ª « « ¬ u Tm , r 5 % absolute or r 30 ms, IEC-NI : IEC-VI : IEC-EI : IEC-LTI : A >IsI @P K = 0.14, D = 0.02 K = 13.5, D = 1.0 K = 80.0, D = 2.0 K = 120.0, D = 1.0 º B » u Tm , r 5 % absolute or r 30 ms, » 1 ¼ for char = ANSI-MI : A = 0.0515, B = 0.114, P = 0.02 ANSI-VI : A = 19.
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7SR242 Duobias Performance Specification 2.11 51G Time Delayed Measured Earth Fault 2.11.1 Reference Parameter Value Is Setting 0.005, 0.10… 1.0 xIn Char Characteristic setting IEC-NI, -VI, -EI, -LTI; ANSI-MI, -VI, -EI; DTL Tm Time Multiplier setting 0.025, 0.05… 1.6 td Delay setting (DTL) 0, 0.01… 20 s tres Reset setting ANSI DECAYING, 0, 1… 60 s I Applied current (for operate time) IDMTL 2 to 20 xIs DTL 5 xIs 2.11.
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7SR242 Duobias Performance Specification 2.11.3 Operate and Reset Time Attribute Value Starter operate time (t 2xIs) 20 ms, r 20ms t op char = IEC-NI, IEC-VI, IEC-EI, IEC-LTI top char = DTL t op ANSI DECAYING ª « « ¬ u Tm , r 5 % absolute or r 30 ms, IEC-NI : IEC-VI : IEC-EI : IEC-LTI : A >IsI @P K = 0.14, D = 0.02 K = 13.5, D = 1.0 K = 80.0, D = 2.0 K = 120.0, D = 1.0 º B » u Tm , r 5 % absolute or r 30 ms, » 1 ¼ for char = ANSI-MI : A = 0.0515, B = 0.114, P = 0.02 ANSI-VI : A = 19.
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7SR242 Duobias Performance Specification 1000 100 Time (sec) 10 Long Time Inverse Normal Inverse 1 Very Inverse Extremely Inverse 0.
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7SR242 Duobias Performance Specification 1000 100 Time (sec) 10 Moderately Inverse 1 Very Inverse Extremely Inverse 0.
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7SR242 Duobias Performance Specification 1000 500 100 50 Extremely Inverse Very Inverse Time (sec) 10 Moderately Inverse 5 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.
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7SR242 Duobias Performance Specification 2.12 59N Neutral Voltage Displacement 2.12.1 Reference (59NDT) Parameter Value Vs Setting 1, 1.5… 100V td Delay setting 0.00, 0.01…20.00, 20.50… 100, 101… 1000, 1010… 10000, 10100… 14400 s 2.12.2 Operate and Reset Level (59NDT) Vop Attribute Value Operate level 100 % Vs, r 2 % or r 0.5 V Reset level t 95 % Vop Repeatability r1% Variation -10 °C to +55 °C d5% fnom - 3 Hz to fnom + 2 Hz d5% 2.12.
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7SR242 Duobias Performance Specification 2.12.
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7SR242 Duobias Performance Specification 2.13 64H Restricted Earth Fault Protection 2.13.1 Reference Parameter Value Is Setting 0.005, 0.010… 0.95 xIn td Delay setting 0.00, 0.01… 20.0, 20.1… 100.0, 101.…1000, 1010 … 10000 , 10100 … 14400 s 2.13.2 Operate and Reset Level Iop Attribute Value Operate level 100 % Is, r 5 % or r1% xIn Reset level 95 % Iop, r 5 % or r0.
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7SR242 Duobias Performance Specification 2.14 81Under/Over Frequency 2.14.1 Reference Parameter Value Fs Setting 40, 40.01… 69.99 Hz Hyst Hysteresis setting 0, 0.1… 80% td Delay setting 0.00, 0.01… 20.0, 20.1… 100.0, 101.…1000, 1010 … 10000 , 10100 … 14400 s 2.14.
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7SR242 Duobias Performance Specification 2.15 87 Biased Differential 2.15.1 Reference Parameter Value ICT Multiplier 1.00x Iinit Initial Setting 0.1, 0.15… 2 xIn IB1 IB1L IB2 st 0.1, 0.15… 0.7 x st 1, 2… 20 xIn 1 Bias Slope setting 1 Bias Slope Limit nd Bias Slope setting 1, 1.05… 2 x nd Bias Slope Type setting Line, Curve 2 IB2T 2 ts Delay setting ©2010 Siemens Protection Devices Limited 0, 0.
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7SR242 Duobias Performance Specification Operate and Reset Level Attribute Value IOPERATE ! I 87 INITIAL SETTING and IOPERATE ! M1 u IRESTRAIN and IOPERATE ! M 2 u IRESTRAIN (for IRESTRAIN ! B) Where Operate level I1 I 2 I OPERATE 2nd Bias Slope Type = Line I1 I 2 IRESTRAIN 2 st B = 87BD 1 Bias slope limit IOP M1 = 87BD 1st Bias slope M2 = 87BD 2nd Bias slope I OPERATE ! I 87 INITIAL SETTING and I OPERATE ! M1 u IRESTRAIN and Operate level I OPERATE 2nd Bias Slope Type = Curve 2 IRESTRA
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7SR242 Duobias Performance Specification 2.16 87HS High-Set Differential 2.16.1 Reference Parameter Value ICT Multiplier 1.00x Is Setting 1, 2 … 30 xIn ts Delay setting 0, 0.005… 1s 2.16.2 Operate and Reset Level Iop Attribute Value Operate level r 5% of setting or r 0.01In Reset level 95% of IOP r 2% Repeatability Transient overreach Variation 5% -10 °C to +55 °C fnom - 3 Hz to fnom + 2 Hz 2.16.
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7SR242 Duobias Performance Specification Section 3: Supervision Functions 3.1 50BF Circuit Breaker Fail 3.1.1 Reference Parameter Value Is Setting: 50BF-n 0.050, 0.055… 2.0 xIn Is Setting: 50BF-n-I4 0.005, 0.010… 2.0 xIn tCBF1 Stage 1 Delay setting 0, 5… 60000ms tCBF2 Stage 2 Delay setting 0, 5… 60000ms 3.1.
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7SR242 Duobias Performance Specification 3.2 74TCS/CCS Trip/Close Circuit Supervision 3.2.1 Reference td Parameter Value Delay setting 0, 0.02…60 s 3.2.
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7SR242 Duobias Performance Specification 3.3 81HBL2 Inrush Detector 3.3.1 Reference Parameter Value Setting I (Ratio of 2nd Harmonic current to 0.10, 0.11... 0.5 Fundamental component current) 3.3.2 Operate and Reset Level Iop Attribute Value Operate level 100 % I, r 4 % or r 1% In Reset level 100 % Iop, r 4 % or r 1% In Repeatability r1% Variation -10 °C to +55 °C d5% fnom - 3 Hz to fnom + 2 Hz d5% 3.3.
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7SR242 Duobias Performance Specification 3.4 81HBL5 Overfluxing Detector 3.4.1 Reference Parameter Value Setting I (Ratio of 5th Harmonic current to 0.10, 0.11... 0.5 Fundamental component current) 3.4.2 Operate and Reset Level Iop Attribute Value Operate level 100 % I, r 4 % or r 1% In Reset level 100 % Iop, r 4 % or r 1% In Repeatability r1% Variation -10 °C to +55 °C d5% fnom - 3 Hz to fnom + 2 Hz d5% 3.4.
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7SR242 Duobias Data Communications 7SR242 Duobias Multi-Function 2-Winding Transformer Protection Relay Document Release History This document is issue 2010/02. The list of revisions up to and including this issue is: 2010/02 Document reformat due to rebrand 2010/02 Third issue. Software revision 2662H80001 R4c-3 2008/07 Second issue. Software revision 2662H80001R3d-2c.
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7SR242 Duobias Data Communications Contents Document Release History....................................................................................................................1 Software Revision History.....................................................................................................................1 Contents ..................................................................................................................................................
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7SR242 Duobias Data Communications Section 1: Introduction The relay data communication facility is compatible with control and automation systems, PCs running Reydisp software can provide operational information, post-fault analysis, settings interrogation and editing facilities. This section describes how to use the Communication Interface with a control system or interrogating computer. Appropriate software within the control system or on the interrogating computer (e.g.
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7SR242 Duobias Data Communications Section 2: Physical Connection The relay provides one ‘Front’ USB communication interface (Com2) located on the fascia and one RS485 (Com1) located on the ‘Rear’. Optional Fibre optic ports can also be located on the rear. Access to the communication settings is only available from the relay front fascia via the COMMUNICATIONS MENU 1. Com2-USB: this port is used for IEC60870-5-103 (default setting) communication with Reydisp software.
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7SR242 Duobias Data Communications 2.1 Communication ports 2.1.1 USB Interface The USB communication port is connected using a standard USB cable with a type B connection to the relay and type A to the PC. The PC will require a suitable USB driver to be installed, this will be carried out automatically when the Reydisp software is installed. When the Reydisp software is running with the USB cable connected to a device an additional connection is shown.
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7SR242 Duobias Data Communications 2.1.2 RS485 Interface The RS485 communication port is located on the rear of the relay and can be connected using a suitable RS485 120 ohm screened twisted pair cable. The RS485 electrical connection can be used in a single or multi-drop configuration. The RS485 master must support and use the Auto Device Enable (ADE) feature. The last device in the connection must be terminated correctly in accordance with the master device driving the connection.
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7SR242 Duobias Data Communications 2.1.3 Fibre Optic Interface When connecting via the optional fibre optic interface the selection of fibre-optic cable is important. Fibres must be terminated with STTM (BFOC/2.5) connectors. The recommended type is 62.5/125μm glass fibre. Communication distances over 1 km are achievable using this type of fibre. The fibre optic data comms link will be interrupted if the relay element is withdrawn from the case.
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7SR242 Duobias Data Communications The following table can be used to record budget calculations: A Launch power dB B Fibre Type C Loss (dB/km) dB/km D Length km E Total fibre loss (CxD) dB F No. of Splices G Loss at each splice dB H Total loss at splices (FxG) dB I No.
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7SR242 Duobias Data Communications Setting name Range Default Station Address 0 … 65534 0 COM3 Protocol OFF, IEC60870-5-103, MODBUS-RTU, DNP3 IEC60870-5103 COM3 Baud Rate 75 110 150 300 600 1200 2400 4800 9600 19200 57600 38400 57600, 115200 The baud rate set on all of the relays connected to the As Required same system must be the same as the one set on the master device.
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7SR242 Duobias Data Communications Rx Rx Tx Tx RS232 to Fibre Optic Converter RS232 straight through cable Computer or Control System USB or 9 pin male D connector 25 pin male D connector Tx Rx Rx Tx 62.
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7SR242 Duobias Data Communications Section 3: IEC 60870-5-103 Definitions 3.1 Introduction This section describes the IEC 60870-5-103 protocol implementation in the relays. This protocol is used for the communication with REYDISP software and can also be used for communication with a suitable control system. The control system or local PC acts as the master in the system with the relay operating as a slave responding to the master’s commands.
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7SR242 Duobias Data Communications Function Informatio Description n Number Function Type Cause of Transmission 60 4 Remote Mode 1 SE, GI, 60 5 Service Mode 1 SE, GI, 60 6 Local Mode 1 SE, GI, 60 7 Local & Remote Mode 1 SE, GI, 60 12 Control Received 1 SE 60 13 Command Received 1 SE 60 128 Cold Start 1 SE 60 129 Warm Start 1 SE 60 130 Re-start 1 SE 60 135 Trigger Storage 1 SE 60 136 Clear Waveform Records 1 SE 60 137 Clear Fault Records 1 SE 6
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7SR242 Duobias Data Communications Function Informatio Description n Number Function Type Cause of Transmission 70 11 Binary Input 11 1 SE, GI, 70 12 Binary Input 12 1 SE, GI, 70 13 Binary Input 13 1 SE, GI, 70 14 Binary Input 14 1 SE, GI, 70 15 Binary Input 15 1 SE, GI, 70 16 Binary Input 16 1 SE, GI, 70 17 Binary Input 17 1 SE, GI, 70 18 Binary Input 18 1 SE, GI, 70 19 Binary Input 19 1 SE, GI, 1 SE, GI, 80 1 Binary Output 1 80 2 Binary Output 2 80
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7SR242 Duobias Data Communications Function Informatio Description n Number Function Type Cause of Transmission 1 SE, GI 20 Ack, Nak Binary Input 1 1 SE, GI 28 Binary Input 2 1 SE, GI 29 Binary Input 3 1 SE, GI 176 30 Binary Input 4 1 SE, GI 176 36 Trip circuit fail 1 SE, GI 176 64 Starter/Pick Up L1 1 SE, GI 176 65 Starter/Pick Up L2 1 SE, GI 176 66 Starter/Pick Up L3 1 SE, GI 176 26 Settings Group 4 Select 176 27 176 176 176 67 Starter/Pick Up N 1 SE,
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7SR242 Duobias Data Communications Function Informatio Description n Number Function Type Cause of Transmission 177 48 37-2 2 SE, GI 177 52 27/59-1 2 SE, GI 177 53 27/59-2 2 SE, GI 177 54 27/59-3 2 SE, GI 177 55 27/59-4 2 SE, GI 177 56 59NIT 2 SE, GI 177 57 59NDT 2 SE, GI 177 58 81-1 2 SE, GI 177 59 81-2 2 SE, GI 177 60 81-3 2 SE, GI 177 61 81-4 2 SE, GI 177 62 81-5 2 SE, GI 177 63 81-6 2 SE, GI 177 64 24DT-1 2 SE, GI 177 65 24DT-2
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7SR242 Duobias Data Communications Function Informatio Description n Number Function Type Cause of Transmission 177 101 CB 1 Total Trip Count 2 177 102 CB 1 Delta Trip Count 2 SE, GI SE, GI 177 103 37G-1 2 SE, GI 177 104 37G-2 2 SE, GI 177 105 Close CB1 2 SE, GI 177 106 CB1 Fail To Close 2 SE, GI 177 107 CB1 DBI 2 SE, GI 177 108 Open CB1 2 SE, GI 177 109 CB1 Fail To Open 2 SE, GI 177 110 Close CB2 2 SE, GI 177 111 CB2 Fail To Close 2 SE, GI 177 112
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7SR242 Duobias Data Communications V,f 178 V (1.2 x) 220 f (1.
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7SR242 Duobias Data Communications Section 4: Modbus Definitions 4.1 Introduction This section describes the MODBUS-RTU protocol implementation in the relays. communication with a suitable control system. This protocol is used for This protocol can be set to use the Fibre Optic and RS485 ports. The relay can communicate simultaneously on all ports regardless of protocol used. Each relay must be given an address to enable communication and can be set by the Communication Interface:Relay Address.
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7SR242 Duobias Data Communications Inputs (Read Only Binary values) Address 10001 10002 10003 10004 10005 10006 10007 10008 10009 10010 10011 10012 10013 10014 10015 10016 10017 10018 10019 10101 10102 10103 10104 10105 10106 10107 10108 10109 10110 10111 10120 10121 10122 10123 10124 10130 10131 10132 10133 10134 10135 10200 10201 10202 10203 10204 10205 10206 10207 10208 10209 10210 10220 10221 10223 10224 10230 10231 10233 10234 10242 10243 Description Binary Input 1 Binary Input 2 Binary Input 3 Binar
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7SR242 Duobias Data Communications 10244 10246 10247 10249 10250 10252 10253 10260 10261 10263 10264 10266 10267 10269 10270 10272 10273 10275 10276 10280 10281 10283 10284 10286 10287 10290 10291 10310 10311 10320 10321 10333 10334 10336 10337 12100 12101 12102 12103 12104 12105 12107 12108 12109 12110 12111 12112 12114 12115 12117 12118 12120 12121 12200 12201 12202 12203 12204 12205 12207 12208 12209 12210 12211 27/59-1 Starter 27/59-2 Operated 27/59-2 Starter 27/59-3 Operated 27/59-3 Starter 27/59-4 O
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7SR242 Duobias Data Communications 12212 12214 12215 12217 12218 12120 12121 12400 12401 12402 12403 12405 12406 12407 12408 12410 12411 12412 12413 12414 12415 12416 12417 12418 12419 12500 12501 12502 12503 12504 12505 12506 12507 12508 12509 12510 12511 12512 12513 12514 12515 12516 12517 12518 12519 12520 12521 12522 12523 12524 12525 12526 12527 12528 12529 12530 12531 12532 12533 12534 12535 12536 12537 12538 50-2 Operated C 51N-2 Starter 51N-2 Operated 50N-2 Starter 50N-2 Operated 51-1 50-1 50BF-1
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7SR242 Duobias Data Communications 12539 12540 12541 12542 12543 12544 12545 12546 12547 12548 12549 12550 12551 12552 12553 12554 12555 12556 12557 12558 12559 12560 12561 12562 12563 12564 12565 12566 12567 12568 12569 12570 12571 12572 12573 12574 12575 12576 12577 12578 12579 12580 12581 12582 12583 12584 12585 Quick Logic E28 Quick Logic E29 Quick Logic E30 Quick Logic E31 Quick Logic E32 Close Circuit Fail 1 Close Circuit Fail 2 Close Circuit Fail 3 Close Circuit Fail 4 Close Circuit Fail 5 Close Ci
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7SR242 Duobias Data Communications Registers Address 30001 30002 30010 30012 30014 Format 1 Register 3 8 Registers UINT16 UINT16 UINT16 30016 30018 Name No.
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7SR242 Duobias Data Communications Address 31208 31210 31212 31214 31216 31218 31220 31222 31224 31226 31228 Name W2 Secondary Ib W2 Secondary Ic W2 Nominal Ia W2 Nominal Ib W2 Nominal Ic W2 Line Ia W2 Line Ib W2 Line Ic W2 Relay Ia W2 Relay Ib W2 Relay Ic Format FP_32BITS_3DP1 1 FP_32BITS_3DP 1 FP_32BITS_3DP FP_32BITS_3DP1 FP_32BITS_3DP1 1 FP_32BITS_3DP 1 FP_32BITS_3DP 1 FP_32BITS_3DP FP_32BITS_3DP1 FP_32BITS_3DP1 1 FP_32BITS_3DP Description A A x Inom x Inom x Inom kA kA kA x Inom x Inom x Inom 32400
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7SR242 Duobias Data Communications Section 5: DNP3.0 Definitions 5.1 Device Profile The following table provides a “Device Profile Document” in the standard format defined in the DNP 3.0 Subset Definitions Document. While it is referred to in the DNP 3.0 Subset Definitions as a “Document,” it is in fact a table, and only a component of a total interoperability guide. The table, in combination with the Implementation Table provided in Section 5.
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7SR242 Duobias Data Communications DNP V3.0 DEVICE PROFILE DOCUMENT (Also see the DNP 3.0 Implementation Table in Section 5.2, beginning on page 28.) Timeouts while waiting for: Data Link Confirm: Complete Appl. Fragment: 7 Application Confirm: Complete Appl. Response: 7 None None None 7 None 7 Fixed - 2sec Fixed at ____ Fixed - 10sec Fixed at ____ Variable Variable Variable Variable Configurable. Configurable Configurable.
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7SR242 Duobias Data Communications DNP V3.0 DEVICE PROFILE DOCUMENT (Also see the DNP 3.0 Implementation Table in Section 5.2, beginning on page 28.
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7SR242 Duobias Data Communications 5.2 Implementation Table The following table identifies which object variations, function codes, and qualifiers the Triangle MicroWorks, Inc. DNP 3.0 Slave Source Code Library supports in both request messages and in response messages. For static (non-change-event) objects, requests sent with qualifiers 00, 01, 06, 07, or 08, will be responded with qualifiers 00 or 01. Requests sent with qualifiers 17 or 28 will be responded with qualifiers 17 or 28.
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7SR242 Duobias Data Communications REQUEST RESPONSE (Library will parse) (Library will respond with) Description Function Qualifier Codes (dec) Codes (hex) Function Qualifier Codes (dec) Codes (hex) Binary Output 1 OBJECT Object Variation Number Number 10 1 (read) 00, 01(start-sto 129 00, 01(start-sto (response) 06(no range, o 17, 28(index – 07, 08(limited q see note 1) 17, 27, 28(inde 10 2 Binary Output Status 1 (write 00, 01(start-sto 1 (read) 00, 01(start-sto 129 00, 01(start-sto
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7SR242 Duobias Data Communications REQUEST RESPONSE (Library will parse) (Library will respond with) Function Qualifier Codes (dec) Codes (hex) Function Qualifier Codes (dec) Codes (hex) OBJECT Object Variation Number Number 30 0 Description Analog Input - Any Variation 1 (read) 00, 01(start-sto 22 (assign class) 06(no range, o 07, 08(limited q 17, 27, 28(inde 30 1 32-Bit Analog Input 1 (read) 00, 01(start-sto 00, 01(start-sto 129 (response) 06(no range, o 17, 28(index – 07, 08(limited q
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7SR242 Duobias Data Communications REQUEST RESPONSE (Library will parse) (Library will respond with) Function Qualifier Codes (dec) Codes (hex) Function Qualifier Codes (dec) Codes (hex) OBJECT Object Variation Number Number Description 51 2 Unsynchronized Time and Date CTO 07(limited qty) 129 (response) (qty = 1) 130 (unsol.
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7SR242 Duobias Data Communications REQUEST RESPONSE (Library will parse) (Library will respond with) Function Qualifier Codes (dec) Codes (hex) Function Qualifier Codes (dec) Codes (hex) OBJECT Object Variation Number Number Description No Object (function code only) 23 (delay meas.) No Object (function code only) 24 (record current time) Note 1: A Default variation refers to the variation responded when variation 0 is requested and/or in class 0, 1, 2, or 3 scans.
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7SR242 Duobias Data Communications 5.3 Point List The tables below identify all the default data points provided by the implementation of the Triangle MicroWorks, Inc. DNP 3.0 Slave Source Code Library. BinaryInput Points The default binary input event buffer size is set to allow 100 events. Note, not all points listed here apply to all builds of devices.
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7SR242 Duobias Data Communications Binary Input Points Static (Steady-State) Object Number: 1 Change Event Object Number: 2 Static Variation reported when variation 0 requested: 2 (Binary Input 2 with status) Change Event Variation reported when variation 0 requested: 3 (Binary Input Change with Relative Time) Point Index Name/Description 42 43 44 45 A-Starter B-Starter C-Starter General Starter 2 2 2 2 2 2 2 2 2 2 2 2 49 Start/Pick-up N 2 2 2 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68
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7SR242 Duobias Data Communications Binary Input Points Static (Steady-State) Object Number: 1 Change Event Object Number: 2 Static Variation reported when variation 0 requested: 2 (Binary Input 2 with status) Change Event Variation reported when variation 0 requested: 3 (Binary Input Change with Relative Time) Point Index Name/Description 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 1
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7SR242 Duobias Data Communications Binary Input Points Static (Steady-State) Object Number: 1 Change Event Object Number: 2 Static Variation reported when variation 0 requested: 2 (Binary Input 2 with status) Change Event Variation reported when variation 0 requested: 3 (Binary Input Change with Relative Time) Point Index Name/Description 145 146 147 148 149 150 151 152 153 154 155 156 Quick Logic E5 Quick Logic E6 Quick Logic E7 Quick Logic E8 Quick Logic E9 Quick Logic E10 Quick Logic E11 Quick Logic
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7SR242 Duobias Data Communications Binary Output Status Points and Control Relay Output Blocks The following table lists both the Binary Output Status Points (Object 10) and the Control Relay Output Blocks (Object 12). While Binary Output Status Points are included here for completeness, they are not often polled by DNP 3.0 Masters. It is recommended that Binary Output Status points represent the most recent DNP “commanded” value for the corresponding Control Relay Output Block (CROB) point.
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7SR242 Duobias Data Communications Binary Output Status Points Object Number: 10 Default Variation reported when variation 0 requested: 2 (Binary Output Status) Control Relay Output Blocks Object Number: 12 Default Default Default Point Name/ Class Variation Event Index Description Variation 36 Settings Group 3 1 2 2 37 Settings Group 4 1 2 2 38 Settings Group 5 1 2 2 39 Settings Group 6 1 2 2 40 Settings Group 7 1 2 2 41 Settings Group 8 1 2 2 1 2 2 1 2 2 1 2 2 1 2
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7SR242 Duobias Data Communications Analog Inputs The following table lists Analog Inputs (Object 30). It is important to note that 16-bit and 32-bit variations of Analog Inputs, Analog Output Control Blocks, and Analog Output Statuses are transmitted through DNP as signed numbers.
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7SR242 Duobias Data Communications Analog Inputs Static (Steady-State) Object Number: 30 Change Event Object Number: 32 Static Variation reported when variation 0 requested: 3 (32-Bit Analog Input w/o Flag), 4 (16-Bit Analog Input w/o Flag) Change Event Variation reported when variation 0 requested: 1 (32-Bit Analog Change Event w/o Time) Default Point Default Default Default Default Event Name/Description Index Class Variation Multiplier Deadband Variation 39 W1 Line Ic 3 2 4 100 1 40 W1 Relay Ia 3 2 4 10
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7SR242 Duobias Data Communications Section 6: Modems The communications interface has been designed to allow data transfer via modems. However, IEC 60870-5-103 defines the data transfer protocol as an 11 bit format of 1 start, 1 stop, 8 data and even parity, which is a mode most commercial modems do not support. High performance modems will support this mode, but are expensive. For this reason, a parity setting is provided to allow use of easily available and relatively inexpensive commercial modems.
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7SR242 Duobias Data Communications 6.1.3 Connecting to the Remote Modem Once the remote modem has been configured correctly, it should be possible to dial up the modem and make connection to the relay. As the settings on the remote modem are fixed the local modem should negotiate with it on connection, choosing suitable matching settings. If it cannot do this, the local modem should be set with settings equivalent to those of the remote modem as described above.
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7SR242 Duobias Data Communications Section 7: Glossary Baud Rate Data transmission speed. Bit The smallest measure of computer data. Bits Per Second (bps) Measurement of data transmission speed. Data Bits A number of bits containing the data. Sent after the start bit. Data Echo When connecting relays in an optical ring architecture, the data must be passed from one relay to the next, therefore when connecting in this method all relays must have the Data Echo ON.
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7SR242 Duobias Installation Guide 7SR242 Duobias Multi-Function 2-Winding Transformer Protection Relay Document Release History This document is issue 2010/02. The list of revisions up to and including this issue is: 2010/02 Document reformat due to rebrand 2010/02 Third issue. Software revision 2662H80001 R4c-3 2008/07 Second issue. Software revision 2662H80001R3d-2c.
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7SR242 Duobias Installation Guide Contents Document Release History....................................................................................................................1 Software Revision History.....................................................................................................................1 Contents ..................................................................................................................................................2 List of Figures..........
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7SR242 Duobias Installation Guide List of Figures Figure 5.1-1 7SR242 Wiring Diagram ....................................................................................................10 Figure 6.1-1 RS485 Data Comms Connections.....................................................................................11 Figure 6.3-1 Data Comms to Multiple Devices Using Sigma 1 and F.O. Star Network .........................12 Figure 6.3-2 Data Comms to Multiple Devices Using Sigma 3 and F.O. Ring Network ......
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7SR242 Duobias Installation Guide Section 1: Installation 1.1 Unpacking, Storage and Handling On receipt remove the relay from the container in which it was received and inspect it for obvious damage. It is recommended that the relay not be removed from its case. If damage has been sustained a claim should be immediately be made against the carrier, also inform Siemens Protection Devices Limited and to the nearest Siemens agent.
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7SR242 Duobias Installation Guide Section 2: Equipment Operating Conditions 2.1 Current Transformer Circuits The secondary circuit of a live CT must not be open circuited. Non-observance of this precaution can result in injury to personnel and/or damage to equipment. ! 2.2 External Resistors Where external resistors are fitted to relays there may be a risk of electric shock or burns if touched. ! 2.
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7SR242 Duobias Installation Guide Section 3: Dimensions and Panel Fixings 3.1 Relay Dimensions and Weight Relays are supplied in size E8 and E10 cases. The drawing below provide panel cut-out and mounting details. Overall Dimensions and panel Drilling for Size E8 Epsilon case (Typically 5.
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7SR242 Duobias Installation Guide 3.2 Fixings 3.2.1 Crimps Ring tongued crimps with 90˚ bend are recommended. 3.2.
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7SR242 Duobias Installation Guide Section 4: Rear Terminal Drawings 4.1 E8 CASE % $ # E8 STANDARD COMMS:- USB FRONT PORT,RS485 (SEE NOTE 2) % $ # E8 STANDARD COMMS + ADDITIONAL PORTS i.e.:- USB FRONT PORT, RS485 (SEE NOTE 2) IRIG B, 2 X F.O. (S.T. CONNECTORS) Notes 1) RECOMMENDED TERMINATIONS ARE PRE-INSULATED & MUST BE CRIMPED USING APPROVED TOOLING. 2) RS485 (BLOCK”B”TERMS 14, 16, 18, 20) CONNECTION TO THIS COMMUNICATION FACILITY IS BY SCREENED, TWISTED PAIR CABLE.
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7SR242 Duobias Installation Guide 4.2 E10 CASE & % $ # & % $ # Notes 1) RECOMMENDED TERMINATIONS ARE PRE-INSULATED & MUST BE CRIMPED USING APPROVED TOOLING. 2) RS485 (BLOCK”B”TERMS 14, 16, 18, 20) CONNECTION TO THIS COMMUNICATION FACILITY IS BY SCREENED, TWISTED PAIR CABLE. ON SITE WHEN WIRING OTHER FACILITIES ENSURE THAT THESE TERMINALS ARE NOT OBSCURED BY OTHER WIRING RUNS. CABLE SHOULD BE RS485 COMPLIANT.
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7SR242 Duobias Installation Guide Section 5: Connection/Wiring/Diagrams 5.1 Wiring Diagram: 7SR242 Relay Figure 5.
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7SR242 Duobias Installation Guide Section 6: Data Comms Connections 6.1 RS485 Connection The RS485 communication port terminals are located on the rear of the relay and can be connected using a suitable RS485 120 screened twisted pair cable. The RS485 electrical connection can be used in a single or multi-drop configuration. The RS485 master must support and use the Auto Device Enable (ADE) feature.
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7SR242 Duobias Installation Guide 6.3 Fibre Optic Connections Where fitted rear Data Comms ports 3 and 4 comprise Fibre–Optic ST™ (BFOC/2.5) bayonet connectors-4 per product. 62.5 / 125 m glass fibre is recommended for all lead lengths. When installing fibre, ensure that the fibres’ bend radii comply with the recommended minimum for the fibre usedtypically 50mm is acceptable. The fibre optic data comms link will be interrupted if the relay element is withdrawn from the case. Figure 6.
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7SR242 Duobias Installation Guide Section 7: Connection Diagrams 7.1 Typical Connection: 7SR242 Figure 7.
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7SR242 Duobias Commissioning & Maintenance Guide 7SR242 Duobias Multi-Function 2-Winding Transformer Protection Relay Document Release History This document is issue 2010/02. The list of revisions up to and including this issue is: 2010/02 Document reformat due to rebrand 2010/02 Third issue. Software revision 2662H80001 R4c-3 2008/07 Second issue. Software revision 2662H80001R3d-2c.
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7SR242 Duobias Commissioning & Maintenance Guide Contents Document Release History....................................................................................................................1 Software Revision History.....................................................................................................................1 Contents ..................................................................................................................................................
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7SR242 Duobias Commissioning & Maintenance Guide 2.11 Under/Over Frequency (81) ....................................................................................................43 2.12 Overfluxing (24) ......................................................................................................................45 2.12.1 definite time (24DT)....................................................................................................45 2.12.2 inverse time (24IT) ............................
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7SR242 Duobias Commissioning & Maintenance Guide List of Figures Figure 2-1 Biased Differential..............................................................................................................14 Figure 2-2 Secondary Injection using a Variac ...................................................................................15 Figure 2-3 Phase Overcurrent.............................................................................................................
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7SR242 Duobias Commissioning & Maintenance Guide Section 1: Common Functions 1.1 Overview Commissioning tests are carried out to prove: a) Equipment has not been damaged in transit. b) Equipment has been correctly connected and installed. c) Prove characteristics of the protection and settings which are based on calculations. d) Confirm that settings have been correctly applied. e) To obtain a set of test results for future reference. 1.2 Before Testing 1.2.
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7SR242 Duobias Commissioning & Maintenance Guide 1.2.3 Test Equipment Required test equipment is: Secondary injection equipment with integral time interval meter Primary injection equipment A d.c. supply with nominal voltage within the working range of the relay's d.c. auxiliary supply rating A d.c. supply with nominal voltage within the working range of the relay’s d.c.
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7SR242 Duobias Commissioning & Maintenance Guide 1.2.5 Applying Settings The relay settings for the particular application should be applied before any secondary testing occurs. If they are not available then the relay has default settings that can be used for pre-commissioning tests. See the Relay Settings section of this manual for the default settings. Note that the tripping and alarm contacts for any function must be programmed correctly before any scheme tests are carried out.
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7SR242 Duobias Commissioning & Maintenance Guide 1.3 Tests 1.3.1 Inspection Ensure that all connections are tight and correct to the relay wiring diagram and the scheme diagram. Record any deviations. Check that the relay is correctly programmed and that it is fully inserted into the case. Refer to ‘Section 2: Settings and Instruments’ for information on programming the relay. 1.3.2 Secondary Injection Tests Select the required relay configuration and settings for the application.
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7SR242 Duobias Commissioning & Maintenance Guide 1.4 AC Energising Quantities Voltage and current measurement for each input channel is displayed in the Instrumentation Mode sub-menus, each input should be checked for correct connection and measurement accuracy by single phase secondary injection at nominal levels. Ensure that the correct instrument displays the applied signal within limits of the Performance Specification.
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7SR242 Duobias Commissioning & Maintenance Guide 1.5 Binary Inputs The operation of the binary input(s) can be monitored on the ‘Binary Input Meters’ display shown in ‘Instruments Mode’. Apply the required supply voltage onto each binary input in turn and check for correct operation. Depending on the application, each binary input may be programmed to perform a specific function; each binary should be checked to prove that its mapping and functionality is as set as part of the Scheme Operation tests.
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7SR242 Duobias Commissioning & Maintenance Guide 1.6 Binary Outputs A minimum of six output relays are provided. Two of these have change over contacts, BO2 & BO3, one has a normally closed contact, BO1 and the remainder have normally open contacts. Care should be observed with regard to connected devices when forcing contacts to operate for test purposes.
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7SR242 Duobias Commissioning & Maintenance Guide Section 2: Protection Functions This section details the procedures for testing each protection function of the 7SR24 relay. These tests are carried out to verify the accuracy of the protection pick-ups and time delays at setting and to confirm correct operation of any associated input and output functionality. Guidance for calculating test input quantities is given in the relevant test description where required.
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7SR242 Duobias Commissioning & Maintenance Guide current or voltage. The resulting composite characteristic may be tested by enabling all of the relevant applicable elements or the element operations can be separated or disabled and tested individually. All relay settings should be checked before testing begins. It is recommended that the relay settings are extracted from the relay using ReyDisp Evolution software and a copy of these settings is stored for reference during and after testing.
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7SR242 Duobias Commissioning & Maintenance Guide 2.1 Biased Differential (87BD, 87HS) Figure 2-1 Biased Differential Voltage Inputs: None Current Inputs: W1-IL1 (IA),W1-IL2 (IB),W1-IL3 (IC), and W2-IL1 (IA),W2-IL2 (IB),W2-IL3 (IC), Disable: 46, 49, 50, 51, 50N, 51N, 50BF, Map Pickup LED: 87BD, 87HS - Self Reset The differential elements are subjected to CT multipliers, Vector Group Compensation and Zero Sequence filters when applied to power transformers.
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7SR242 Duobias Commissioning & Maintenance Guide Secondary testing of the bias characteristic will be greatly simplified by the use of automated numeric protection test equipment such as the Omicron CMC256. This equipment can be programmed using setting which match those of the relay to test for accuracy over the whole operating range and give a clear easy to use graphical display of relay performance against the specified characteristic.
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7SR242 Duobias Commissioning & Maintenance Guide 2.1.1.2 Results for testing 87BD with 2 current sources 87BD INITIAL SETTING 0.10 0.20 0.30 0.40 0.50 0.50 0.50 Selected Settings 87BD 1ST BIAS SLOPE SETTING W1 CURRENT (X IN) 0.00 1.00 W2 Current (x In) 0.1 1.11 0.2 1.22 0.3 1.35 0.4 1.5 0.5 1.67 0.5 1.86 0.5 2.08 Test Results 0.00 1.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 1.50 2.00 2.50 1.66 1.83 2.03 2.25 2.5 2.79 3.12 2.21 2.44 2.71 3.0 3.33 3.71 4.15 2.76 3.06 3.38 3.75 4.17 4.64 5.19 1.
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7SR242 Duobias Commissioning & Maintenance Guide 2.1.2 Primary Injection Testing Primary injection is recommended to prove the relay connections, CT polarity and settings before putting the protection scheme into service. Primary injection is essential to fully prove the connections of the Biased Differential and REF protections. To provide a useful test the relay should have the final site specific settings applied for primary injection tests.
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7SR242 Duobias Commissioning & Maintenance Guide 2.1.3 Phase Overcurrent (50, 51) Figure 2-3 Phase Overcurrent Voltage Inputs: None Current Inputs: W1-IL1 (IA), W1-IL2 (IB), W1-IL3 (IC), or W2-IL1 (IA), W2-IL2 (IB), W2-IL3 (IC), Disable: 46, 49, 50BF, 87BD, 87HS Map Pickup LED: 51-n/50-n - Self Reset Other protection functions may overlap with these functions during testing, it may be useful to disable some functions to avoid ambiguity.
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7SR242 Duobias Commissioning & Maintenance Guide 2.1.4 Definite Time Overcurrent (50) If DTL setting is small, gradually increase current until element operates. If DTL is large apply 0.9x setting, check for no operation, apply 1.1x setting, check operation Apply 2x setting current if possible and record operating time Phas e IL1(IA) Dir. Is (Amps) DTL (sec) P.U. Current Amps Operate Time 2 x Is NOTES IL2(IB) IL3(IC) Check correct indication, trip output, alarm contacts, waveform record. 2.1.
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7SR242 Duobias Commissioning & Maintenance Guide 2.1.5.1 Element Blocking The Phase Overcurrent elements can be blocked by Binary Input Inhibit and Inrush Detector operation. This functionality should be checked. Element BI Inhibits Inrush Detector 51-1 51-2 50-1 50-2 2.1.5.2 ANSI Reset If the element is configured as an ANSI characteristic, it may have an ANSI (decaying) reset delay applied. If ANSI reset is selected for an IEC characteristic element, the reset will be instantaneous.
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7SR242 Duobias Commissioning & Maintenance Guide 2.2 Derived Earth fault (50N,51N) Figure 2-4 Measured Earth Fault Voltage Inputs: None Current Inputs: W1-IL1 (IA), W1-IL2 (IB), W1-IL3 (IC), or W2-IL1 (IA), W2-IL2 (IB), W2-IL3 (IC), Disable: 50BF, 50, 51, 49, 37 Map Pickup LED: 51N-n/50N-n - Self Reset Other protection functions may overlap with these functions during testing, it may be useful to disable some functions to avoid ambiguity.
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7SR242 Duobias Commissioning & Maintenance Guide 2.2.1 Definite Time Overcurrent (50N) If DTL setting is small, gradually increase current until element operates. If DTL is large apply 0.9x setting, check for no operation, apply 1.1x setting, check operation Apply 2x setting current if possible and record operating time Input Is (Amps) DTL (sec) P.U. Current Amps Operate Time 2 x Is NOTES Check correct indication, trip output, alarm contacts, waveform record. 2.2.
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7SR242 Duobias Commissioning & Maintenance Guide 2.2.2.1 Element Blocking The Measured Earth Fault elements can be blocked by Binary Input Inhibit, VT Supervision and Inrush Detector operation. The Characteristic can be made non-directional by VT Supervision. This functionality should be checked. Element BI Inhibits Inrush Detector 51N-1 51N-2 51N-3 51N-4 50N-1 50N-2 50N-3 50N-4 2.2.3 ANSI Reset If the element is configured as an ANSI characteristic, it may have a reset delay applied.
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7SR242 Duobias Commissioning & Maintenance Guide 2.3 Measured Earth fault (50G, 51G) Figure 2-5 Measured Earth Fault Voltage Inputs: None Current Inputs: IG1 , IG2 Disable: 50BF, 64H Map Pickup LED: 51G-n/50G-n - Self Reset Other protection functions may overlap with these functions during testing, it may be useful to disable some functions to avoid ambiguity. Derived EF, Measured EF & Restricted EF protections can be Enabled/Disabled individually or as groups in the ‘Function Config’ menu.
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7SR242 Duobias Commissioning & Maintenance Guide 2.3.1 Definite Time Overcurrent (50G) If DTL setting is small, gradually increase current until element operates. If DTL is large apply 0.9x setting, check for no operation, apply 1.1x setting, check operation Apply 2x setting current if possible and record operating time Input Is (Amps) DTL (sec) P.U. Current Amps Operate Time 2 x Is NOTES IG1 Check correct indication, trip output, alarm contacts, waveform record. 2.3.
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7SR242 Duobias Commissioning & Maintenance Guide 2.3.2.1 Element Blocking The Measured Earth Fault elements can be blocked by Binary Input Inhibit, VT Supervision and Inrush Detector operation. The Characteristic can be made non-directional by VT Supervision. This functionality should be checked. Element BI Inhibits Inrush Detector 51G-1 51G-2 51G-3 51G-4 50G-1 50G-2 50G-3 50G-4 2.3.3 ANSI Reset If the element is configured as an ANSI characteristic, it may have a reset delay applied.
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7SR242 Duobias Commissioning & Maintenance Guide 2.4 Restricted Earth fault (64H) Figure 2-6 Restricted Earth Fault Voltage Inputs: n/a Current Inputs: IG1 , IG2 Disable: 50G, 51G, 50BF Map Pickup LED: 64H-n - Self Reset The external stabilising resistor value should be measured and compared to that specified in the settings data. Both values should be recorded.
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7SR242 Duobias Commissioning & Maintenance Guide These elements can be enabled for the IG1 or IG2 current inputs by relay settings, ensure that current is injected on the correct input. Since the DTL setting is generally small the pick-up setting can be tested by gradually increasing current until element operates. The relay should be disconnected from the current transformers for this test. Apply 2x setting current if possible and record operating time Is (Amps) DTL (sec) P.U.
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7SR242 Duobias Commissioning & Maintenance Guide 2.5 Open Circuit (46BC) Figure 2-7 Open Circuit Voltage Inputs: n/a Current Inputs: W1-IL1 (IA), W1-IL2 (IB), W1-IL3 (IC), or W2-IL1 (IA), W2-IL2 (IB), W2-IL3 (IC), Disable: 51N, 46IT, 46DT Map Pickup LED: 46BC - Self Reset This function uses the ratio of NPS current to PPS current to detect an open circuit . These quantities can be produced directly from many advanced test sets but with limited equipment the following approach can be applied.
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7SR242 Duobias Commissioning & Maintenance Guide 46BC Setting 1P unbalance current (% of 3P current) 46BC Setting 20% 75% 25% 100% 30% 129% 35% 161% 40% 200% 3P balanced current (A) 1P unbalance current (A) Measured Unbalance current 46BC-1 46BC-2 Apply 1A 1P unbalance current without 3P balanced current. Measure 46BC operating time. 46BC Delay setting Measured 46BC-1 46BC-2 2.5.1.
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7SR242 Duobias Commissioning & Maintenance Guide 2.6 Negative Phase Sequence Overcurrent (46NPS) Figure 2-8 Negative Phase Sequence Overcurrent Voltage Inputs: n/a Current Inputs: W1-IL1 (IA), W1-IL2 (IB), W1-IL3 (IC), or W2-IL1 (IA), W2-IL2 (IB), W2-IL3 (IC), Disable: 50, 51, 50BF, 87BD Map Pickup LED: 46IT/46DT - Self Reset Where two NPS elements are being used with different settings, it is convenient to test the elements with the highest settings first.
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7SR242 Duobias Commissioning & Maintenance Guide 2.6.1 Definite Time NPS Overcurrent (46DT) If DTL setting is small, gradually increase current until element operates. If DTL is large apply 0.9x setting, check for no operation, apply 1.1x setting, check operation Apply 2x setting current if possible and record operating time Phase Is (Amps) DTL (sec) P.U. Current Amps Operate Time 2 x Is NOTES NPS Check correct indication, trip output, alarm contacts, waveform record. 2.6.
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7SR242 Duobias Commissioning & Maintenance Guide 2.6.2.1 ANSI Reset If the element is configured as an ANSI characteristic, it may have a reset delay applied. If ANSI reset is selected for an IEC characteristic element, the reset will be instantaneous. ANSI reset times from operated condition to fully reset are as follows for zero applied current and TM = 1.0. The reset curve characteristic type and TM is defined by the operating characteristic.
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7SR242 Duobias Commissioning & Maintenance Guide 2.7 Undercurrent (37, 37G) Figure 2-9 Undercurrent 2.7.1 Voltage Inputs: n/a Current Inputs: W1-IL1 (IA), W1-IL2 (IB), W1-IL3 (IC), IG1 or W2-IL1 (IA), W2-IL2 (IB), W2-IL3 (IC), IG2 Disable: 50N, 51N, 51G, 46, 87BD Map Pickup LED: 37-n, 37G-n - Self Reset 37-n Elements If two Undercurrent 37 elements are used with different settings, it is convenient to test the element with the lowest setting first.
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7SR242 Duobias Commissioning & Maintenance Guide Apply 0.5x setting current and record operating time Phase Is (Amps) DTL (sec) P.U. Current Amps Operate Time 0.5 x Is NOTES Wn-IL1(IA) Wn-IL2(IB) Wn-IL3(IC) Wn-IL1(IA) Wn-IL2(IB) Wn-IL3(IC) Elements can be blocked by operation of a Binary Input Inhibit or by operation of the 37-n U/I Guard element. This functionality should be checked.
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7SR242 Duobias Commissioning & Maintenance Guide 2.8 Thermal Overload (49) Figure 2-10 Thermal Overload Voltage Inputs: n/a Current Inputs: W1-IL1 (IA), W1-IL2 (IB), W1-IL3 (IC), or W2-IL1 (IA), W2-IL2 (IB), W2-IL3 (IC), Disable: 51, 50, 37, 46NPS, 50CBF, 87BD Map Pickup LED: 49 Alarm The current can be applied from a 3P balanced supply or phase by phase from a 1P supply. Alternatively the 3 phase current inputs can be connected in series and injected simultaneously from a single 1P source.
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7SR242 Duobias Commissioning & Maintenance Guide Time Constant (mins) Operate Time (sec) 1 17.3 2 34.5 3 51.8 4 69 5 86.3 10 173 15 259 20 345 25 432 30 51.8 50 863 100 1726 The Thermal State must be in the fully reset condition in order to measure the operate time correctly. This can be achieved by setting change in the Thermal protection settings menu or by pressing the Test/Reset button when the Thermal Meter is shown in the Instruments Mode.
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7SR242 Duobias Commissioning & Maintenance Guide 2.9 Under/Over Voltage (27/59) Figure 2-11 Phase Under/Over Voltage Voltage Inputs: V1 (VX) Current Inputs: n/a apply zero current to stabilize other functions Disable: Map Pickup LED: 59N 27/59-n - Self Reset Where more than one Undervoltage (27) elements are being used with different settings, it is convenient to test the elements with the lowest settings first.
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7SR242 Duobias Commissioning & Maintenance Guide When testing is complete reinstate any of the disabled functions. Where more than one Overvoltage (59) elements are being used with different settings, it is convenient to test the elements with the highest settings first. The elements with lower settings can then be tested without disabling the higher settings. If the ‘O/P Phases’ is set to ‘All’, the voltage on all phases must be increased simultaneously.
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7SR242 Duobias Commissioning & Maintenance Guide 2.9.2 Undervoltage Guard (27/59UVG) If any 27 Undervoltage element is set to be inhibited by the 27 Undervoltage Guard element, this function should be tested. Connect the test voltage inputs to suit the installation wiring diagram utilising any test socket facilities available. It may be useful to temporarily map an LED as ‘General Pickup’ to assist during testing. 27UVG operation will reset the General Pickup if no other element is operated.
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7SR242 Duobias Commissioning & Maintenance Guide 2.
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7SR242 Duobias Commissioning & Maintenance Guide 2.10.1 Definite Time (59NDT) If DTL setting is small, gradually increase single phase voltage until element operates. If DTL is large apply 0.9x setting, check for no operation, apply 1.1x setting, check operation Apply 2x setting voltage if possible and record operating time Phase Vs (Volts) DTL (sec) P.U. Current Volts Operate Time 2 x Vs NOTES V1(VX) Check correct indication, trip output, alarm contacts, waveform record. 2.10.
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7SR242 Duobias Commissioning & Maintenance Guide 2.11 Under/Over Frequency (81) Figure 2-13 Under/Over Frequency Voltage Inputs: V1 (VX) Current Inputs: n/a apply zero current to stabilize other functions Disable: Map Pickup LED: 81-n - Self Reset For Over-frequency, the elements with the highest setting should be tested first and for Under-frequency the elements with the lowest settings should be tested first.
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7SR242 Duobias Commissioning & Maintenance Guide The frequency should then be gradually decreased/increased until the element resets. The reset frequency can be used to check the Hysteresis setting. If the element is set as 81-n U/V Guarded, The applied voltage must be above the 81 UV Guard Setting in the U/O Frequency menu. Apply setting frequency +0.5Hz for Over-frequency or -0.5Hz for Under-frequency and record operating time.
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7SR242 Duobias Commissioning & Maintenance Guide 2.12 Overfluxing (24) Figure 2-14 Under/Over Frequency The settings are set in terms of V/f based on multiple of nominal voltage and frequency. Application of a voltage of nominal voltage and frequency represents 1.0. Testing is simplified by applying nominal frequency and increasing voltage only, such that the operating level is simply the setting multiplied by Nominal Voltage. 2.12.
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7SR242 Duobias Commissioning & Maintenance Guide 2.12.2 inverse time (24IT) The inverse V/f element should be tested at each of the points specified by settings that constitute the overall inverse characteristics. Setting (xVn) Setting (volts) Hysteresis (%) Calculated D.O. (volts) X0 Setting (xVn) Setting (volts) X1 DTL Setting (sec) Y1 X2 Y2 X3 Y3 X4 Y4 X5 Y5 X6 Y6 ©2010 Siemens Protection Devices Limited Operate Time DTL Setting (sec) Y0 P.U. Volts D.O.
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7SR242 Duobias Commissioning & Maintenance Guide Section 3: Supervision Functions 3.
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7SR242 Duobias Commissioning & Maintenance Guide These elements are operated from W1 and W2 current inputs, ensure that current is injected on the correct input for the element being tested. Apply a trip condition by injection of current to cause operation of a suitable protection element. Allow current to continue after the trip at a level of 110% of the 50BF Setting current level on any phase. Measure the time for operation of 50BF-1 Delay and 50BF-2 Delay.
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7SR242 Duobias Commissioning & Maintenance Guide 3.2 Trip/Close Circuit Supervision (74TCS, 74CCS) Figure 3-2 Trip Circuit Supervision Voltage Inputs: n/a Current Inputs: n/a Disable: Map Pickup LED: 74TCS-n/74CCS-n - Self Reset The T/CCS-n Delay can be initiated by applying an inversion to the relevant status input and measured by monitoring of the alarm output.
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7SR242 Duobias Commissioning & Maintenance Guide 3.3 Magnetising Inrush Detector (81HBL2) Figure 3-3 Magnetising Inrush Detector Voltage Inputs: n/a Current Inputs: W1-IL1 (IA), W1-IL2 (IB), W1-IL3 (IC), or W2-IL1 (IA), W2-IL2 (IB), W2-IL3 (IC) Disable: Map Pickup LED: Logical operation of the harmonic blocking can be tested by injection of 2nd harmonic current (at 100Hz for 50Hz relay) to cause operation of the blocking signals.
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7SR242 Duobias Commissioning & Maintenance Guide A compromise test can be made by the use of a diode to generate a half-wave rectified waveform from a sinusoidal source. The half-wave rectified current will contain a combination of fundamental and harmonic currents. The rectified waveform contains even harmonics higher than 2nd but the relationship between the 2nd harmonic current content, the fundamental component and the total RMS current is as shown below.
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7SR242 Duobias Commissioning & Maintenance Guide 3.4 Overfluxing Detector (81HBL5) Figure 3-4 Magnetising Inrush Detector Voltage Inputs: n/a Current Inputs: W1-IL1 (IA), W1-IL2 (IB), W1-IL3 (IC), or W2-IL1 (IA), W2-IL2 (IB), W2-IL3 (IC) Disable: Map Pickup LED: Logical operation of the harmonic blocking can be tested by injection of 5th harmonic current (at 250Hz for 50Hz relay) to cause operation of the blocking signals.
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7SR242 Duobias Commissioning & Maintenance Guide Section 4: Control & Logic Functions 4.1 Quick Logic If this functionality is used, the logic equations may interfere with testing of other protection functions in the relay. The function of the Quick Logic equations should be tested conjunctively with connected plant or by simulation to assess suitability and check for correct operation on an individual basis with tests specifically devised to suit the particular application.
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7SR242 Duobias Commissioning & Maintenance Guide Section 5: Testing and Maintenance 7SR24 relays are maintenance free, with no user serviceable parts. 5.1 Periodic Tests During the life of the relay, it should be checked for operation during the normal maintenance period for the site on which the product is installed. It is recommended the following tests are carried out:1. Visual inspection of the metering display 2. Operation of output contacts 3. Secondary injection of each element 5.
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7SR242 Duobias Commissioning & Maintenance Guide Observation Action Cannot communicate with the relay. Check that all of the communications settings match those used by ReyDisp Evolution. Check that the Tx and Rx fibre-optic cables are connected correctly. ( Tx –> Rx and Rx –> Tx ). Check that all cables, modems and fibre-optic cables work correctly. Ensure that IEC 60870-5-103 is specified for the connected port (COM1, COM2, COM3 or COM4). Relays will not communicate in a ring network.
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7SR242 Duobias Commissioning & Maintenance Guide 5.4 Defect Report Please copy this sheet and use it to report any defect that may occur.
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7SR242 Duobias Applications Guide 7SR242 Duobias Multi-Function 2-Winding Transformer Protection Relay Document Release History This document is issue 2010/02. The list of revisions up to and including this issue is: 2010/02 Document reformat due to rebrand 2010/02 Third issue. Software revision 2662H80001 R4c-3 2008/07 Second issue. Software revision 2662H80001R3d-2c.
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7SR242 Duobias Applications Guide Contents Document Release History....................................................................................................................1 Software Revision History.....................................................................................................................1 Contents ..................................................................................................................................................
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7SR242 Duobias Applications Guide 5.4.1 5.4.2 Trip Circuit Supervision Connections .........................................................................46 Close Circuit Supervision Connections......................................................................48 Section 6: Application Considerations and Examples .....................................................................49 6.1 The Effects of An In Zone Earthing Transformer ..................................................................
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7SR242 Duobias Applications Guide List of Figures Figure 1-1 Example Use of Alternative Settings Groups ......................................................................5 Figure 1-2 Example of Transformer Alarm and Trip Wiring .....................................................................6 Figure 1-3 – Binary Input Configurations Providing Compliance with EATS 48-4 Classes ESI 1 and ESI 2 ...........................................................................................................
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7SR242 Duobias Applications Guide Section 1: Common Functions 1.1 Multiple Settings Groups Alternate settings groups can be used to reconfigure the relay during significant changes to system conditions e.g. Primary plant switching in/out. Summer/winter or day/night settings. switchable earthing connections. Allowable short term overloads.
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7SR242 Duobias Applications Guide 1.2 Binary Inputs Each Binary Input (BI) can be programmed to operate one or more of the relay functions, LEDs or output relays. These could be used to bring such digital signals as Inhibits for protection elements, the trip circuit supervision status, autoreclose control signals etc. into the Relay. Alarm and Tripping Inputs A common use of binary inputs is to provide indication of alarm or fault conditions e.g. transformer Buchholz Gas or Buchholz Surge conditions.
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7SR242 Duobias Applications Guide The Effects of Capacitance Current The binary inputs have a low minimum operate current and may be set for instantaneous operation. Consideration should be given to the likelihood of mal-operation due to capacitance current. Capacitance current can flow through the BI, for example if an earth fault occurs on the dc circuits associated with the relay.
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7SR242 Duobias Applications Guide Figure 1-3 – Binary Input Configurations Providing Compliance with EATS 48-4 Classes ESI 1 and ESI 2 ©2010 Siemens Protection Devices Limited Chapter 7 Page 8 of 56
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7SR242 Duobias Applications Guide 1.3 Binary Outputs Binary Outputs are mapped to output functions by means of settings. These could be used to bring out such digital signals as trips, a general pick-up, plant control signals etc. All Binary Outputs are trip rated Each can be defined as Self or Hand Reset. Self-reset contacts are applicable to most protection applications. Hand-reset contacts are used where the output must remain active until the user expressly clears it e.g.
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7SR242 Duobias Applications Guide Section 2: Protection Functions This section provides guidance on the application and recommended settings of the 7SR24 protection functions. 2.1 Overall Differential Protection (87) This section covers the transformer overall differential protections – the biased differential and high-set differential elements.
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7SR242 Duobias Applications Guide 2.1.1 ICT Settings for Current Magnitude Balance Internal current multipliers are used to adjust the CT secondary currents to accommodate for any mismatch between the winding 1 and winding 2 CT ratios. For load or through fault conditions the output of the ICT Multiplier for each winding must be equal, notwithstanding variations in the OLTC position.
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7SR242 Duobias Applications Guide Interposing CT Selection Guide Power Transformer Vector Group HV Interposing CT Selection LV Interposing CT Selection Yy0, YNy0, Yyn0, YNyn0, Ydy0, Yndy0, Ydyn0, Yndyn0, Dz0 Ydy0,0q Ydy0,0q Yd1, YNd1 Yd1,-30q Yy0,0q Yd1, YNd1 + Earthing Transformer Yd1,-30q Ydy0,0q Yy2, YNy2, Yyn2 YNyn2, Ydy2, YNdy2, Ydyn2, Yndyn2, Dz2 Ydy2,-60q Ydy0,0q Yd3, YNd3 Yd3,-90q Yy0,0q Yd3, YNd3 + Earthing Transformer Yd3,-90q Ydy0,0q Yy4, YNy4, Yyn4, YNyn4, Ydy4, YNdy4, Ydy
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7SR242 Duobias Applications Guide 2.1.3 Biased Differential (87BD) Settings The 87BD elements provide differential protection for phase and earth faults. The limiting factors for protection sensitivity are dictated by the need to ensure protection stability during load or through fault conditions. Magnitude restraint bias is used to ensure the relay is stable when the transformer is carrying load current and during the passage of external (out of zone) fault current.
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7SR242 Duobias Applications Guide When a through fault occurs, saturation of one or more CTs may cause a transient differential current to be detected by the relay. The bias slope limit is chosen to ensure the biased differential function is stable for high through fault currents coincident with CT saturation. This setting defines the upper limit of the bias slope and is expressed in multiples of nominal rated current i.e. the lower the setting the more stable the protection.
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7SR242 Duobias Applications Guide 2.1.4 Differential Highset (87HS) Settings The element operates on the differential current measured by the relay. The 87HS element is generally applied as an unrestrained differential element to provide fast tripping for heavy internal faults.
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7SR242 Duobias Applications Guide 2.1.5 Example 1 – New Installation Figure 2-4 New Transformer Application The required AC connections to the 7SR24 are shown in fig. 2.
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7SR242 Duobias Applications Guide Step 1 – Selection of Line CT Ratios CTs with a secondary rating of 1A are preferred as the burden imposed on the CT by the secondary wiring is reduced in comparison with a 5A rated secondary. HV load current = LV load current = 90 u 10 6 393.7A 3 u 132,000 90 u 10 6 3 u 33,000 A CT ratio of 400/1A is chosen. u 0.95 1495.7 A A CT ratio of 1600/1A is chosen. Note, the 0.95 factor relates to the tap changer at mid-tap position.
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7SR242 Duobias Applications Guide Summary of Required Settings CT/VT CONFIG > W1 Phase Input W1 Phase CT Ratio W2 Phase Input W2 Phase CT Ratio 1A 400:1 1A 1600:1 FUNCTION CONFIG> Gn Differential Gn Inrush Detector Enabled Enabled DIFFERENTIAL PROT’N > Gn W1 ICT Multiplier 1.02 Gn W1 ICT Connection Yd11 Gn W2 ICT Multiplier 1.07 Gn W2 ICT Connection Yy0 (Note that the above settings produce ICTOUT = 1.00) DIFFERENTIAL PROT’N > 87BD > Gn 87 BD Element Gn 87BD Initial: Gn 87BD 1st Bias Slope: 0.
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7SR242 Duobias Applications Guide 2.1.5.1 Example 1 – Further Analysis Having established settings to ensure stability under load, transient and external fault conditions the following considers the operating levels for internal faults.
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7SR242 Duobias Applications Guide W1 Internal Phase-Phase Fault Figure 2-8: Relay Currents - Star Winding Internal Phase Fault Notes B - C fault causes current to flow in the A, B and C elements The Yd ICT connection causes a 1:2:1 current distribution and introduces a 1/ 3 multiplying factor.
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7SR242 Duobias Applications Guide W2 Internal Earth Fault Figure 2-9: Relay Currents - Delta Winding Internal Earth Fault W2 Internal Phase-Phase Fault Figure 2-10: Relay Currents - Delta Winding Internal Phase Fault ©2010 Siemens Protection Devices Limited Chapter 7 Page 21 of 56
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7SR242 Duobias Applications Guide Table 2-1 summarises the implications of using Yd or Yy interposing CTs. Table 2-1 The Effect of ICT Selection on Protection Settings CT HV LV Secondary ( ICT: Yd11, x 1.02) ( ICT: Yy0, x 1.07) Current W1 ICTOUT = W2 ICTOUT = 3-Phase A = 1A A = 1.02A A = 1.07A B = 1A B = 1.02A B = 1.07A C = 1A C = 1.02A C = 1.07A A=0 A = 0.589A A=0 B = 1A B = 1.178A B = 1.07A C = 1A C = 0.589A C = 1.07A A = 1A A = 0.589A A = 1.07A B=0 B=0 B=0 C=0 C = 0.
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7SR242 Duobias Applications Guide 2.1.6 Example 2 – Relay Replacement Using Existing CTs Figure 2-11 Relay Replacement It is recommended to wire all line CTs in star when connecting to the 7SR24 relay. Where the 7SR24 is used to replace an older biased differential relay the existing CTs will often be re-used, it is recommended that any line CTs connected in ‘delta’ are reconnected as ‘star’.
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7SR242 Duobias Applications Guide Step 1 – Connection of CTs Remove all interposing CTs from the secondary circuit. Connect all line CT secondary wiring in star. HV load current = LV load current = 45 u 10 6 196.8A 3 u 132,000 45 u 10 6 3 u 33,000 Re-use 300/1A CTs. u 0.95 747.9A Re-use 560/0.577A CTs. Step 2 – Selection of Interposing CT Multiplier Settings HV Secondary current = 196.8 300 LV Secondary current = 747.9 560 / 0.577 0.66A 0.77 A HV ICT Multiplier = 1/0.66 = 1.
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7SR242 Duobias Applications Guide Summary of Protection Settings CT/VT CONFIG > W1 Phase Input W1 Phase CT Ratio W2 Phase Input W2 Phase CT Ratio 1A 300:1 1A 560:0.58 FUNCTION CONFIG> Gn Differential Gn Inrush Detector Enabled Enabled DIFFERENTIAL PROT’N > Gn W1 ICT Multiplier 1.54 Gn W1 ICT Connection Yy0 Gn W2 ICT Multiplier 1.30 Gn W2 ICT Connection Yd11 (Note that the above settings produce ICTOUT = 1.00) DIFFERENTIAL PROT’N > 87BD > Gn 87 BD Element Gn 87BD Initial: Gn 87BD 1st Bias Slope: 0.
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7SR242 Duobias Applications Guide 2.2 Instantaneous OC/EF (50/50G/50N) Instantaneous overcurrent can be applied to protect the HV terminals against high fault currents. The current setting applied must be above the maximum 3-phase through fault level of the transformer to ensure grading with the LV overcurrent protection. Where the setting applied is below the magnetising inrush current of the transformer then inrush blocking (81HBL2) should be enabled. 2.
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7SR242 Duobias Applications Guide 1000.00 1000.00 100.00 100.00 10.00 Operating Time (Seconds) Operating Time (Seconds) 10.00 1.00 1.00 0.10 0.10 0.01 0.01 1 10 100 1 1000 10 100 1000 Current (x Is) Current (x Is) Figure 2-14 IEC NI Curve with Time Multiplier and Follower DTL Applied 1000.00 100.00 Operating Time (Seconds) 10.00 1.00 0.10 0.
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7SR242 Duobias Applications Guide 2.3.2 Reset Delay Faults in plastic insulated cables or compound-filled joint boxes can be intermittent or ‘flashing’ faults – the insulant melts and temporarily reseals the fault for a short time after which the insulation fails again. The repeating process of the fault often causes electromechanical disc relays to “ratchet” up and eventually trip the faulty circuit if the reset time of the relay was longer than the time between successive flashes.
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7SR242 Duobias Applications Guide 2.4 High Impedance Restricted Earth Fault (64H) Restricted earth fault (REF) protection can be applied to either or both windings of the transformer. The 7SR24 provides a high impedance REF (64H) element for each transformer winding. Low leakage reactance CTs (Class PX) are required for use with high impedance protection systems.
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7SR242 Duobias Applications Guide The relay current setting is calculated taking into account: the required operate level for in-zone earth faults (fault setting). Determination of Stability The stability of the high impedance REF scheme depends upon the operate voltage setting being greater than the maximum voltage which can appear across the element/stabilising resistor during the maximum assigned through fault conditions. It is assumed that any earthing resistor can become short-circuit.
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7SR242 Duobias Applications Guide 2.5 Open Circuit (46BC) Used to detect an open circuit condition e.g. an OLTC failure. There will be little or no fault current and so differential elements will not detect the condition. However the condition can be detected because there will be a high content of NPS (unbalance) current present. An NPS / PPS ratio > 50% will result from an open circuit condition. A time delay can be applied to prevent operation for transitory effects. 2.
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7SR242 Duobias Applications Guide 2.8 Thermal Overload (49) Thermal protection is provided to supplement the Winding Temperature device. This function provides a general overload thermal protection i.e. not a winding hot spot protection. Outputs can be assigned to both alarm and trip levels. The default settings are recommended if transformer data is not available, these settings correspond to the lowest level of thermal withstand for an oil filled transformer.
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7SR242 Duobias Applications Guide 49 Capacity Alarm Setting This setting can be used to provide an alarm prior to a thermal trip occurring and is typically set to about 80 to 90 % of thermal capacity. The thermal capacity alarm can be mapped to a binary output wired to the control system. Example Figure 2-19 Thermal Overload Settings 1. In fig. 2-19 the direction of power flow is HV to LV. If W1 input is connected to HV CTs (as is usual) then set 49 Select = W1.
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7SR242 Duobias Applications Guide 2.9 Under/Over Voltage (27/59) Power system under-voltages may occur due to: System faults. An increase in system loading, Non-energized power system e.g. loss of an incoming transformer During normal system operating conditions regulating equipment such as transformer On Load Tap Changers (OLTC) and generator Automatic Voltage Regulators (AVR) ensure that the system runs within acceptable voltage limits.
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7SR242 Duobias Applications Guide 2.10 Neutral Overvoltage (59N) Neutral Overvoltage Displacement (Residual Overvoltage) protection is used to detect an earth fault where little or no earth current flows. This can occur where a transformer feeder has been tripped at its HV side for an earth fault, but the circuit is still energised from the LV side via an unearthed transformer winding.
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7SR242 Duobias Applications Guide 2.10.1 Application with Capacitor Cone Units Capacitor cones provide a cost effective method of deriving residual voltage. The wide range of capacitor cone component values used by different manufacturers means that the relay cannot be connected directly to the cones.
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7SR242 Duobias Applications Guide 2.11 Under/Over Frequency (81) During normal system operation the frequency will continuously vary over a relatively small range due to the changing generation/load balance. Excessive frequency variation may occur for: Loss of generating capacity, or loss of mains supply (underfrequency): If the governors and other regulating equipment cannot respond to correct the balance, a sustained underfrequency condition may lead to a system collapse.
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7SR242 Duobias Applications Guide 2.12 Over Fluxing Protection (24) An underfrequency condition at nominal voltage can cause over-fluxing (or over-excitation) of the transformer. Excess flux can cause transformer core saturation and some of the flux will radiate as leakage flux through the 2 transformer tank. This leakage flux causes eddy currents and the I R losses from these currents heat the transformer tank and can cause overheating.
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7SR242 Duobias Applications Guide Section 3: CT Requirements The specification of CTs must meet the requirements of all protection functions utilised e.g. overall differential, REF and backup over current protections. The relay has 1A and 5A rated terminals for each CT input and any combination of these may be used. 1A rated CTs can be used on one winding and together with 5A rated CTs on the other. 3.
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7SR242 Duobias Applications Guide Worked Example Figure 3-1 CT Requirements Suitability of HV Current Transformers: VK t 4 u 90 u 10 6 3 u 132 u 10 3 u 400 u 0.14 u 3.5 1 126.5V u 12 4 449.9V i.e. less than 250V Suitability of LV Current Transformers: VK t 4 u 90 u 10 6 3 u 33 u 10 3 u1600 u 0.14 i.e. less than 750V An indication of the suitability of a protection class CT e.g. class 5P to IEC60044 classification can be obtained.
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7SR242 Duobias Applications Guide Section 4: Control Functions 4.1 User Defined Logic 4.1.1 Auto-Changeover Scheme Example Figure 4-1 Example Use of Quick Logic The MV installation illustrated above is fed from two incomers. To limit the substation fault level the busbar is run with CB3 open. When a fault occurs on one of the incomers it is isolated by the circuit protection. To re-supply the disconnected loads from the remaining incomer CB3 is closed.
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7SR242 Duobias Applications Guide Section 5: Supervision Functions 5.1 Inrush Detector (81HBL2) 87 Inrush Element (Enable, Disable) When a transformer is energized transient magnetizing inrush currents flow in each phase of the energised winding. Inrush currents only flow into one transformer winding and the resulting unbalance can be sufficient to cause mal-operation of the biased differential elements.
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7SR242 Duobias Applications Guide The recommended settings for each method are: Phase – 0.18 x Id Cross – 0.20 x Id Sum – 0.15 x Id These setting provide a good compromise between speed of operation for internal faults and stability for inrush current. Generally the above values will be stable for most cases, but in rare cases may not prevent relay operation for all angles of point on wave switching, and the setting may require being lower slightly.
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7SR242 Duobias Applications Guide 5.3 Circuit Breaker Fail (50BF) Where a circuit breaker fails to operate to clear fault current the power system will remain in a hazardous state until the fault is cleared by remote or back-up protections. To minimise any delay, CB Failure protection provides a signal to either re-trip the local CB or back-trip the next ‘upstream’ CB.
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7SR242 Duobias Applications Guide Relay Operation and CBF Timer Started System Fault Backtrip Trip Relay Operation CBF Retrip Trip Relay Main Trip Relay Operation 40 CB's Fails to Trip 60 80 No Reset of CBF elements No Reset of CBF elements CBF Retrip Operation Reset of CBF elements CBF Back trip Operation Failed CB Retrip Operation 100 120 140 Operation of all BB CB's 160 180 200 220 240 260 280 300 320 340 360 ms from occuri CB Operate Time Stage 1 CBF Timer (Retrip) = 120ms S
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7SR242 Duobias Applications Guide 5.4 Trip Circuit Supervision (74TCS) Binary Inputs may be used to monitor the integrity of the CB trip circuit wiring. Current flows through the B.I. confirming the integrity of the auxiliary supply, CB trip coil, auxiliary switch, C.B. secondary isolating contacts and associated wiring connected to that BI. If the current flow ceases, the B.I. drops off and if it is user programmed to operate one of the output relays, this can be used to provide an alarm.
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7SR242 Duobias Applications Guide Scheme 2 (Intermediate) BO + 52a TRIP COIL - TRIP CCT n FAIL 52a Circuit Breaker BI R +ve -ve 52b BO 1 BO n Remote Alarm Figure 5-5: H6 Scheme Notes: Resistor: 30V dc Nominal: 48V dc Nominal: 110V dc Nominal: R = 3K9 R = 5K6 R = 15K0 Trip Circuit Supervision Scheme 2 (H6) Scheme 2 provides continuous Trip Circuit Supervision of trip coil with the circuit breaker Open or Closed.
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7SR242 Duobias Applications Guide 5.4.2 Close Circuit Supervision Connections BO + 52a CLOSE COIL - CLOSE CCT n FAIL R BI +ve Circuit Breaker R -ve 52b BO 1 BO n Remote Alarm Resistor: 30V dc Nominal: 48V dc Nominal: 110V dc Nominal: R = 3K9 R = 5K6 R = 15K0 Figure 5-7 Close Circuit Supervision Scheme Close circuit supervision with the circuit breaker Open or Closed.
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7SR242 Duobias Applications Guide Section 6: Application Considerations and Examples 6.1 The Effects of An In Zone Earthing Transformer Yy0 (0o) Yd11 (30o) The in zone earthing transformer is a source of zero-sequence fault current.
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7SR242 Duobias Applications Guide Figure 6-2: Relay Currents – External Earth Fault with In Zone Earthing Transformer Figure 6-3 7SR24 Applied to Yd Transformer with an In Zone Earthing Transformer ©2010 Siemens Protection Devices Limited Chapter 7 Page 50 of 56
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7SR242 Duobias Applications Guide 6.2 Protection of Star/Star Transformer With Tertiary Winding Figure 6-4: The provision of the tertiary winding in star/star transformers both stabilises the neutral potential and can allow earth fault current to flow in the secondary connections i.e. reduces the zero sequence impedance.
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7SR242 Duobias Applications Guide 6.3 Transformer with Primary Connections Crossed on Both Windings Yd11 Transformer Connected as Yd9 (900) The phase-shift between the W1 and W2 primary systems may necessitate that primary connections to each winding of the transformer have to be crossed. Fig. 6.4-1 shows a typical arrangement where a Yd11 transformer is arranged to give a primary system phase-shift of 90q by crossing of its main connections. There are two optional methods of configuring the 7SR24 relay.
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7SR242 Duobias Applications Guide Solution 2 Figure 6.4-2 shows use of the ICT Connection settings to correct for the phase shift introduced by the transformer connection i.e. ICT1 Connection is set to to Yd9, -90° and ICT2 Connection is set to Ydy0, 0°.
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7SR242 Duobias Applications Guide 6.4 Transformer with Primary Connections Crossed on One Winding Reversing the connections on only one side of the transformer will reverse the phase sequence of the system. For this arrangement W1 and W2 CT secondary wiring must be crossed over to replicate the crossovers on the transformer primary connections – see fig. 6.5-1.
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7SR242 Duobias Applications Guide 6.5 Protection of Auto Transformers The transformer has a phase shift of zero. To prevent undesired tripping of the overall differential protection for external faults a zero sequence shunt is required, this is implemented by selecting star/delta ICT Connection settings. The ICT Connection setting on all both sets of CT inputs must be the same e.g. all Yd1, -30° or all Yd11, 30°.
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7SR242 Duobias Applications Guide 6.6 Reactor and Connections Protection 1 A 2 W1 IL1 2 6 6 5 W1 IL2 9 5 W2 IL2 10 W1 IL3 13 B 1 W2 IL1 14 IG1 ICT1 = Yy0 10 9 W2 IL3 18 A 17 IG2 ICT2 = Yy0 Figure 6-10 AC Connections for Reactor and Connections Protection Settings must take into consideration: Connections: High internal and through fault currents. Series reactor: Through fault current limited by reactor. Shunt reactor: Single end fed faults only.
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