® 1625 Earth/Ground Tester Users Manual January 2006 © 2006 Fluke Corporation, All rights reserved. Printed in USA All product names are trademarks of their respective companies.
LIMITED WARRANTY AND LIMITATION OF LIABILITY Each Fluke product is warranted to be free from defects in material and workmanship under normal use and service. The warranty period is two years and begins on the date of shipment. Parts, product repairs, and services are warranted for 90 days.
Table of Contents Title Introduction .......................................................................................... Models and Accessories........................................................................ Safety Instructions ................................................................................ Qualified Staff .................................................................................. Setup ..................................................................................
1625 Users Manual Measurement of Interference - Voltages and Frequencies................ Measurement of Earthing Resistances.............................................. 3-pole/4-pole Measurement of Earthing Resistance ..................... Measurement of Single Earth Electrode Resistances in Mesh Operated Earthing Systems Using Selective Clamp Method ......................................................................................... 3-pole/4-pole Measurement of Single Earth Electrode Resistances ...
List of Tables Table 1. 2. 3. Title Page Models and Accessories ................................................. 3 Electrical Measurement Specifications .......................... 14 Description of Displays..................................................
1625 Users Manual iv
List of Figures Figure 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. Title Fluke 1625 Earth/Ground Tester.................................... Description of Functions ................................................ Display ........................................................................... Operating Elements ........................................................ Display Elements ........................................................... Operational Modes ............
1625 Users Manual vi
Earth/Ground Tester Introduction At locations involving the generation, distribution and consumption of electrical energy, certain safety measures must be met in order to protect human life. In many cases, these safety measures are national and international regulations which must be checked regularly. Grounding, the connection of exposed conductive parts to the earth in case of a fault, represents the most fundamental safety measure.
1625 Users Manual Notes • The terms earth and earthing also refer to ground and grounding and is used interchangeably throughout this manual. • For stakeless earth resistance measurements, the EI-1625 must be purchased. (The EI-1625 comes standard with the 1625 Kit). Refer to Appendix A for a complete set of operating information including specifications. • Selective measurements are described in the main section of this manual.
Earth/Ground Tester Models and Accessories Models and Accessories Table 1 lists the models and accessories. Table 1.
1625 Users Manual Safety Instructions W Warning This measuring equipment is only to be operated by qualified staff and in accord with its technical data in compliance with the safety precautions and instructions set forth below. In addition, use of this equipment requires compliance with the legal and safety instructions pertaining to the specific application in question. Similar precuations apply to the use of accessories.
Earth/Ground Tester Setup Qualified Staff Consists of persons familiar with the setting up, assembly, starting up and operation of the product and possess the qualifications required for such activities, such as • training, instruction and/or authorization to perform the following operations on circuits and equipment according to safety engineering standards: switching on and off, disconnecting, earthing/grounding, labeling; • training or instructions according to safety engineering standards in the car
1625 Users Manual General Microprocessor controlled universal earth resistance meter with fully automated measuring frequency selection process as well as automatic testing of probe- and auxiliary earth electrode resistances and possible interference voltages as per DIN IEC61557-5/EN61557-5.
Earth/Ground Tester Assembly Assembly The instrument is made up of two parts: 1. The base part which contains the measuring electronics. 2. The protective housing. The functions are selected with the central rotary switch. Four rubber buttons, which start measurements, read out supplementary measuring values and select special functions, are located on the left hand side of the front panel. This design enables quick and clear one-hand operation.
25 Users Manual EXT H S ES E Switching Voltage measurement ADC Comp Current measurement Processor Relais driver Undervoltage detection Source LCD driver Supply voltage Display Rotary selector switch buttons edw003.eps Figure 2. Description of Functions Measurement of Interference Voltage (UST) Fullwave rectification for DC and AC (DC without operational sign, AC signal sinus calibrated for r.m.s. values). If limit values are exceeded no measurement will be started.
Earth/Ground Tester Description of Functions Measurement of Earthing Resistance (RE) The earthing resistance is determined by a 3- or 4-pole current and voltage measurement. The measuring voltage is a square pulse AC voltage with 48 / 20 V and a frequency of 94, 105, 111 or 128 Hz. The frequency can be selected manually or automatically (AFC). Selective Measurement of Earthing Resistance (RE A) Measurement of a single earth electrode in a mesh operated (parallel) earthing system.
1625 Users Manual LO-BAT Supervision of the battery charge status is done with a comparator circuit. Via microprocessor, a drop in battery capacity down to typ. 10 % of its specified value is indicated on the display with symbol LO-BAT.
Earth/Ground Tester Specifications Operation: Central rotary switch and function keys Working temperature range: -10 °C … +50 °C Operating temperature range: 0 °C … +35 °C Nominal temperature range: 18 °C … +28 °C Storage temperature range: -30 °C … +60 °C Note The chart of four temperature ranges for the instrument exist to satisfy European Standards requirements; the instrument can be used over the full Working temperature range by using the temperature coefficient to calculate accuracy at t
1625 Users Manual Max voltage: Wsocket A to socket EFGH Urms = 0 V Sockets ” E ES S H " to each other in any combination, max. Urms= 250 V (pertains to misuse) EMC (Emission Immunity): IEC 61326-1:1997 Class A Quality standard: developed, designed and manufactured to comply with DIN ISO 9001 External field influence: complies with DIN 43780 (8/76) Auxiliary power: 6x Battery life span: with IEC LR6/type AA: typ.
Earth/Ground Tester Specifications Measurement of Interference Voltage DC + AC (UST) Measuring method: Measuring Range 1…50 V Display Range 0.0…50 V fullwave rectification Resolution Frequency Range Limits of Error 0.1 V DC/AC 45…400 Hz sine ± (5% of reading +5 digit) Measuring sequence: approx. 4 measurements /s Internal resistance: approx. 1.5 MΩ Max.
1625 Users Manual Table 2. Electrical Measurement Specifications Requirements or Test in Accordance with the Relevant Parts of IEC 1557 Intrinsic Error or Influence Quantity Reference Conditions or Specified Operating Range Intrinsic error Reference conditions A Part 5, 6.1 R Position Reference position ± 90° E1 Part 1, 4.2 R Supply voltage At the limits stated by the manufacturer E2 Part 1, 4.2, 4.3 R Temperature 0 °C and 35 °C E3 Part 1, 4.2 T Series interference voltage See 4.
Earth/Ground Tester Specifications A = intrinsic error En = R = routine test T = type test Measuring Range B[%] = ± variations Display Range Resolution 0.001 Ω...2.999 Ω 0.001 Ω 3.00 Ω...29.99 Ω 0.01 Ω 0.020 Ω 30.0 Ω...299.9 Ω 0.1 Ω 300 kΩ 0.300 kΩ...2.999 kΩ 1Ω 3.00 kΩ...29.99 kΩ 10 Ω 30.0 kΩ...299.9 kΩ 100 Ω Measuring time: B x 100% fiducial value Instrinsic Error ± ( 2 % of mv +2 digit ) Max. Operating Error ± ( 5% of mv +5 digit ) typ. 8 sec.
1625 Users Manual fluencing conditions (see diagramm), the display shows a warning symbol W and a notice that RS or RH are too high. F 3000 1000% 1000 RH/RE= 300 100 100 % 30 10 10% 3 1 1% 0,3 0,1% 10 10 0 1k 10k 1 00k 1M RS edw005.
Earth/Ground Tester Specifications Selective Measurement of the Earthing Resistance (REA) Measuring method: Current and voltage measurement with probe as per EN61557-5 and current measurement in the individual branch with additional current transformer (patent applied for). Open circuit voltage: 20 / 48 V AC Short circuit current: 250 mA AC Measuring frequency: 94, 105, 111, 128 Hz selected manually or automatically (AFC), 55 Hz (R*) Noise rejection: 120 dB (16 2/3 , 50 , 60 , 400 Hz) Max.
1625 Users Manual Minimal current in single branch to be measured: Max. interference current through transformer: 0.5 mA with transformer (1000:1) 0.1 mA with transformer (200:1) 3A with a transformer (1000:1) Resistance Measurement (R~) Measuring method: current and voltage measurement Measuring voltage: 20 V AC, square pulse Short circuit current: > 250 mA AC Measuring frequency: 94, 105, 111, 128 Hz selected manually or automatically (AFC) Measuring Range Display Range Resolution 0.
Earth/Ground Tester Specifications Resistance Measurement (RF) Measuring method: current- voltage measurement as per IEC61557-4 possible Open circuit voltage: 20 V DC Short circuit current: 200 mA DC Formation of measured value: with 4-pole measurement wires on H, S, ES can be extended without additional error. Resistances >1 Ω in wire E can cause additional error of 5m Ω/Ω. Measuring Range Display Range Resolution 0.001 Ω ... 2.999 Ω 0.001 Ω 0.020 Ω 3.0 Ω ... 29.99 Ω 0.01 Ω 3 kΩ 30.0 Ω ..
1625 Users Manual Compensation of Lead Resistance (RK) Compensation of lead resistance (RK) can be switched on in functions RE 3pole, RE 4pole A, R~ , and R F 2pole Formation of measured value: Rdisplay = Rmeasured - Rcompensated* * Value of setpoint entry RK = 0.000Ω, variable from 0.000…29.99 Ω by means of measuring adjustment.
Earth/Ground Tester Description of the Operating Elements Description of the Operating Elements Figure 4 illustrates the operating elements described below. 6 2 7 1625 EARTH / GROUND TESTER START TEST 3 H/C2 DISPLAY MENU 8 S/ P2 Earth/Ground Resistance 300k RA AC Resistance 300 k DC Low Resistance 3k R R 2 POLE 4 POLE 3 POLE 4 POLE CHANGE ITEM 4 3 POLE 9 2 POLE 4 POLE ES/ P1 OFF SELECT 10 E /C1 5 11 1 rear side 12 13 edw006.eps Figure 4.
1625 Users Manual D "CHANGE ITEM" button to change the set point entry values. E "SELECT" button to select the digit to be changed. F Display unit, liquid crystal digits, 18 mm high with automatic decimal point as well as active illumination. G Connecting socket H (auxiliary earth electrode) (4 mm ø) also usable with safety measuring lead H Connecting socket G (probe) (4 mm ø) also usable with safety measuring lead. I Connecting socket for an ext. clip-on current transformer (optional).
Earth/Ground Tester Description of the Operating Elements Description of Display Elements The display (Figure 5) is divided into four display elements: 1. Digital display of measured value 2. Measuring function field to display measuring function 3. Unit field: V, Ω, kΩ, Hz 4. Special characters for operator guidance 2 1 3 4 edw008.eps Figure 5.
1625 Users Manual R~ AC- resistance * R Earthing impedance (measuring frequency 55 Hz) AFC Automatic-frequency-control TEST Measuring sequence in process LIMIT Limit value > LIMIT Limit value exceeded EFGH Socket recognition B Recognition of current transformer socket } Message of an exceeded limit with beeper LO-BAT Battery voltage too low, replace batteries.
Earth/Ground Tester Procedure of Measurements POWER ON Functions During switching on of the instrument with the central rotary switch it is possible to access certain operating conditions by pressing certain button combinations: a) Standard mode If the device is put into operation without further button control, it switches into a battery saving condition (Stand by-display "---") approx. 50 seconds after the termination of a measurement, or after a button push or turn of the rotary switch.
1625 Users Manual e) Activation of display illumination By keeping the "CHANGE ITEM" button pressed during the switch on sequence the display illumination is activated. Illumination fades away automatically if the instrument is switched to"Stand by" and, together with the instrument, is switched on again by pressing any button. The instrument is switched off with ON/OFF on the central rotary switch exclusively.
Earth/Ground Tester Procedure of Measurements CONTROL LOOP ON/OFF MEASURING LOOP POWER ON Function SELECT MEASURING FUNTION WITH CENTRAL ROTARY SWITCH 1 X DISPLAY LIMIT SET VALUE OR VOLTAGE MEASUREMENT 1 X CHANGE QUICK SWITCHOVER, SET VALUE 1 X START MEASUREMENT DISPLAY, MEASURED VALUE OR SUPPLEMENTARY VALUE 1 X DISPLAY 1 X SELECT DIGIT/DECIMAL POINT SPOT SELECTION 1 X CHANGE INCREASE SELECTED SPOT (DIGIT/DECIMAL POINT) BY 1 edw009.eps Figure 6.
1625 Users Manual Control Loop After turning the function rotary switch, the voltage display mode is reached. Pushing "DISPLAY MENU" now calls up the control loop. According to the selected measuring function, different setting values can be displayed and changed in the control loop. The "DISPLAY MENU" button switches between the different set values inside a contiuous loop. The "SELECT" button selects the decimal point to be changed.
Earth/Ground Tester Procedure of Measurements A UM 48 V/20 V selectable to 20 V with CODE and RK 0.000 Ω ... 29.99 Ω in position RE 3pole only * RE 4pole I ( ratio ) 80 ... 1200 display only RE LIMIT 0.000 Ω ...
1625 Users Manual Measuring Loop This loop is entered by pressing the "START TEST" button. After releasing "START TEST" the last measured value stays on the display. By repeated pressing of the "DISPLAY MENU" button all supplementary values can be called. If a measured value exceeds or falls below the pre-set limit, the limit can be displayed as well (with "DISPLAY MENU"). In that case the measured value is diplayed with a flashing "LIMIT" whereas the limit value is displayed with a steady "LIMIT"-symbol.
Earth/Ground Tester Procedure of Measurements Safety Control Measurements Before each measurement the instrument automatically checks the measuring conditions and, while simultaneously displaying the kind of error, prevents measurements from being started under the following conditions: • excessive voltage on the sockets (> 24 V in RE and R~; > 3 V in RF) • wrong or incomplete connection • Problems during the measuring sequence (display "E1 ...
1625 Users Manual 1625 EARTH / GROUND TESTER START TEST H /C2 DISPLAY MENU S/P2 Earth/Ground Resistance 300 k AC Resistance 300 k DC Low Resistance 3k RA R R 2 POLE 4 POLE 3 POLE 4 POLE CHANGE ITEM 3 POLE 2 POLE 4 POLE ES/P1 OFF SELECT E /C1 Earth electrode >20 m Probe Auxiliary earth electrode >20 m edw010.eps Figure 7.
Earth/Ground Tester Procedure of Measurements To keep the instrument as simple as possible at the time of delivery, all special functions, such as LIMIT input, BEEPER programming, measurement of earthing impedance (R*) etc, are not activated at delivery. They can be activated with personalized user's code (see "Changing of all Pre-set Data with Personalized Code"). Refer to Figure 8. Umeas. G I I E S E UE RE H S RS H RH edw011.eps Figure 8.
1625 Users Manual 1625 EARTH / GROUND TESTER START TEST H/C2 DISPLAY MENU S/P2 Earth/Ground Resistance 300k AC Resistance 300 k DC Low Resistance 3k RA R R 2 POLE 4 POLE 3 POLE 4 POLE CHANGE ITEM 3 POLE 4 pole 2 POLE 4 POLE ES/P1 OFF SELECT E /C1 Earth electrode >20 m Probe Auxiliary earth electrode >20 m edw012.eps Figure 9. 3-pole/4-pole Measurement of Earthing Resistance - Process 1.
Earth/Ground Tester Procedure of Measurements An accuracy test of the results is made with another measurement following repositioning of the auxiliary earth electrode or probe. If the value stays the same, the distance is sufficient. If the measured value changes, probe or auxiliary earth electrode must be repositioned until the measured value RE stays constant. Spike wires should not run too close to each other.
1625 Users Manual Measurement of Single Earth Electrode Resistances in Mesh Operated Earthing Systems Using Selective Clamp Method This measuring method has been created to measure single earth electrodes in permanently wired or mesh operated systems (e.g. lightning protection system with several electrodes or high voltage pylons with earth cabling etc.).
Earth/Ground Tester Procedure of Measurements Errors of the current transformer can be corrected as described in “Correcting Clip-on Transformer Error”. 3-pole/4-pole Measurement of Single Earth Electrode Resistances See Figure 12.
1625 Users Manual Note The ratio that is preset from factory is correct for the EI162X sensing clamp Press "START TEST" button. Now a fully automated test sequence of all relevant parameters like auxiliary earth electrode, probe- and earth electrode resistance, is implemented and finished with the display of the result RE. 1. Read out measured value RE 2. Call RS and RH with "DISPLAY MENU".
Earth/Ground Tester Procedure of Measurements reliable values, the instrument offers the possibility of averaging over a longer period. 1. Select a fixed frequency (see "Control loop", Operation) 2. Keep the "START TEST" button pressed until the warning "measured value unstable" disappears. Max. averaging time is approx. 1 min.
1625 Users Manual Accordingly, these equivalent resistances are displayed as: R Ei = U meas li Therefore the earthing resistance RE of the pylon is determined as a parallel circuit of the individual equivalent resistances: RE = 1 1 1 1 1 + + + R E1 R E 2 R E 3 R E 4 1625 EARTH / GROUND TESTER START TEST H/C2 DISPLAY MENU S/P2 Earth/Ground Resistance 300 k RA AC Resistance 300 k R DC Low Resistance 3k R 2 POLE 4 POLE 3 POLE 4 POLE CHANGE ITEM 3 POLE 2 POLE 4 POLE ES/P1 OFF SELECT E /C1
Earth/Ground Tester Procedure of Measurements 3. Press “START TEST” button Now a fully automated test sequence of all relevant parameters like auxiliary earth electrode, probe- and earth electrode resistance, is implemented and finishes with the display of the result RE. 4. Read out measured value RE 5. Call RS and RH with “DISPLAY MENU”.
1625 Users Manual Time average measurement: If there is a warning "measured value unstable" (see "Description of displays", Procedure of Measurement) after a test sequence, most likely it is caused by strong interference signals (e.g. unsteady noise voltage). Nevertheless, to get reliable values, the instrument offers the possibility of averanging over a longer period. 1. Select a fixed frequency (see "Control loop", Operation) 2.
Earth/Ground Tester Procedure of Measurements 1625 EARTH / GROUND TESTER START TEST H/C2 DISPLAY MENU S/P2 Earth/Ground Resistance 300 k AC Resistance 300 k RA DC Low Resistance 3k R R 2 POLE 4 POLE 3 POLE 2 POLE 4 POLE 4 POLE CHANGE ITEM ES/P1 3 POLE OFF E /C1 SELECT edw017.eps Figure 14. Correcting Clip-on Transformer Errors 2. Turn central rotary switch to position "A RE 3pole". 3. Press "START TEST"-button and note result of RE value. 4. Connect clip-on transformer.
1625 Users Manual Example: Your clip-on transformer has a transformation ratio of tr = 1000:1. The measurement without clip-on transformer results in a value RE = 0.983 Ω . With a clip-on transformer a value of RE = 1.175 Ω is measured. The deviation thus reads (1.175 - 0.983) Ω= + 0.192 Ω and referring to RE = 0.983 Ω an error evolves as following: 100% × 0.192Ω = +19.5% 0.983Ω The new transformation ratio to be set calculates: 1.175 = 1195 0.
Earth/Ground Tester Procedure of Measurements 3. Call display RK with "DISPLAY MENU" button. 4. Implement compensation with "START TEST" button. The compensation resistance is displayed only for as long as the "START TEST" button is kept pressed.
1625 Users Manual 1. Four earth spikes of the same length are positioned into the soil in an even line and with the same distance "a" to each other. The earth spikes should not be hammered in deeper than a maximum of 1/3 of "a". 2. Turn central rotary switch to position "RE 4pole". The instrument is to be wired according to picture and notices given on the display. A flashing of the sockets symbols EFGH or B, points to an incorrect or incomplete connection of the measuring lead. 3.
Earth/Ground Tester Procedure of Measurements 1 3 Soil restivity E 2 A Distances of Probe edw021.eps Curve 1: As ρE decreases only deeper down, a deep earth electrode is advisable Curve 2: As ρE decreases only down to point A, an increase in the depth deeper than A does not improve the values. Curve 3: With increasing depth ρE is not decreasing: a strip conductor electrode is advisable.
1625 Users Manual O 90 E ES S H I edw022.eps Measurement of Resistances Resistance Measurement (R~) This measuring function determines the ohmic resistance between 0.001 Ω and 300 kΩ. The measurement is done with AC voltage. For measurements of very low resistances a compensation of the connecting leads is suggested (see “Compensation of Measuring Lead Resistance”).
Earth/Ground Tester Procedure of Measurements 2. Connect instrument according to picture. 3. In this mode, all settings and LIMIT values available can be called with "DISPLAY MENU" and the measuring frequency can be set. 4. Press "START TEST" button. 5. Read out measured value. Resistance Measurement (RF) In this measuring mode all resistances from 0.001 Ω to 3 kΩ can be measured with DC voltage and automatic polarity reversal as per EN61557-5.
1625 Users Manual W Warning Due to the high measuring current inductive loads can cause lethal induced voltages during disconnection from the measuring circuit. 4. Start measurement with "START TEST" button. First, "R1" with positive voltage is measured on jack "E". After releasing the "START TEST" button "R2" is measured with negative voltage on jack "E". The respectively higher measured value is displayed first. 5. The second measured value can be called with "DISPLAY MENU".
Earth/Ground Tester Procedure of Measurements Turning the central rotary switch for a short moment deletes the line compensation again. 1625 EARTH / GROUND TESTER START TEST H/C2 DISPLAY MENU S/P2 Earth/Ground Resistance 300 k RA AC Resistance 300 k R DC Low Resistance 3k R 2 POLE 4 POLE 3 POLE 4 POLE CHANGE ITEM 3 POLE 2 POLE 4 POLE ES/P1 OFF SELECT E /C1 edw026.eps Figure 20.
1625 Users Manual Function Parameter Standard presetting Setting range FM (AFC/94/105/111/128) Hz AFC UM 48 V/20 V 48V RK 0.000 Ω ... 29.99 Ω 0.000 Ω LIMIT On / Off Off RE LIMIT 0.000 Ω ... 999 kΩ 999 kΩ }(Warning sound) On/Off Off R* On/Off Off FM (AFC/94/105/111/128) Hz AFC RE 3pole UM 48 V/20 V 48V A RK 0.000 Ω ... 29.99 Ω 0.000 Ω and I ( ratio ) 80 ... 1200 1000 RE 4pole LIMIT On/Off Off A RE LIMIT 0.000 Ω ...
Earth/Ground Tester Procedure of Measurements RF 2pole RK 0.000 Ω ... 29.99 Ω 0.000 Ω and LIMIT On/Off Off 4pole R LIMIT 0.000 Ω ... 9,99 kΩ 9.99 kΩ }(Warning sound) On/Off Off Storing a Code 1. Press all 4 keys simultaneously and move central selector from OFF to the desired measuring mode. The display shows "C _ _ _". 2. Now enter the CODE-number. Any three-digit number can be entered.
1625 Users Manual 6. The changed value is stored by pressing the "DISPLAY MENU" key. 7. Pressing the "START TEST" key exits the setting program. Note If the limit values required by regulations are changed incorrect, erroneous test results may be displayed. Deleting a Code 1. Press all 4 keys simultaneously and move central selector from OFF to any measuring mode. The display shows " C _ _ _ ". 54 2. Now enter the existing CODE-number. 3.
Earth/Ground Tester Description of Displays Description of Displays Table 3. Description of Displays Function Displays Before "START" Condition Note Stand by position to reduce power consumption Turn rotary switch or push button. All measured values remain stored No or incorrect measuring lead connection Apart from voltage measurement all measuring functions are locked. Battery voltage too low Replace batteries. Beeper on Acoustical warning if limit is exceeded. edw027.eps ST V edw028.
1625 Users Manual Function Displays V ST Condition Note Dangerous AC - voltage > 50 V Apart from voltage measurement all measuring functions are locked. Rotary switch in intermediate position Select correct position. Probe resistance is being tested Wait for test result. Aux. current spikeresistance is being tested. Wait for test result. Earth resistance is being tested. Wait for test result. LIMIT edw031.eps Before "START" edw033.eps After "START" S TEST edw034.eps H TEST edw035.
Earth/Ground Tester Description of Displays Function Displays Condition V ST edw037.eps V ST edw038.eps K H LIMIT edw039.eps After "START" k E Note Measuring circuit of earth- and auxil. earth electrode disconnected. Check lead connection on earth spikes measuring lead might be defective. Measuring circuit of earth- and probe electrode disconnected. Check lead connection on earth spikes measuring lead might be defective.
1625 Users Manual Function Displays Condition E LIMIT Note Display of measured value exceeds LIMIT. Measured value is higher than set LIMIT. Compensation higher than measured value. Delete compensation or switch instrument ON/OFF. Wrong polarity on jacks E and ES. Reverse polarity. Measured value instable. Unsteady noise voltage. Try time average measurement. Current in external transformer to low. Reduce auxiliary current spike resistance. edw041.eps K LIMIT edw042.eps ST edw043.
Earth/Ground Tester Description of Displays Function Displays No reactions to button control etc. Condition Note Operation under faulty conditions. Check batteries. Switch ON/OFF if still faulty, contact service. Reverse orientation of current clamp or "upwards" current. Reverse clamp or see note on page 28. edw046.eps After "START" E edw047.eps Checksum of EE PROM incorrect. edw048.eps Hardware malfunction (e.g. current overload). edw049.
1625 Users Manual Function Displays Condition EE PROM memory access malfunction. Note contact service. edw050.eps Internal computation malfunction. edw051.eps Thermal overload. Cool thoroughly. edw052.eps VmA k Hz nFmH ST E 12MKH REMOTE LO-BAT TEST LIMIT edw053.eps Battery voltage decreases at measurement. The internal resistance of the batteries is too high (worn out, low temperature). Replace batteries, warm up instrument.
Earth/Ground Tester Care and Maintenance detergent or spirit. Avoid aggressive cleaning agents and solvents (trilene, chlorothene etc.). Service work must only be undertaken by trained qualified staff. In all repair work care must be taken that the design parameters of the instrument are not modified to the detriment of safety, that assembled parts correspond to the original spares and that they are reassembled properly (factory state).
1625 Users Manual Recalibration This instrument exceeds the prescribed accuracies by multiples as it leaves the factory. To maintain it in this state, we recommend a check at 1-year intervals. Please contact the nearest sales or service center for this purpose. As an extra service feature we offer you periodic checking and calibration of your meters. You may order, for a fee, either company test certificates or test certificates of the public calibration service at your option.
Stakeless Earth/Ground Resistance Testing Care and Maintenance Appendix A Stakeless Earth/Ground Resistance Testing Introduction Stakeless testing provides the ground tester with the unique capability to measure individual ground resistances in multi-grounded systems using two clampon current transformers. The use of ground stakes is not necessary.
1625 Users Manual edw060.eps Specifications General: Adapter unit for use with ground testers in the mode: RE D 3 pole (Order No. EI-1625) All information contained in this section exclusively refers to this application. Principle: Ground testing without using earth stakes for the probe and the auxiliary earth electrode. Working temperature range –10 °C ... +55 °C. Operating temperature range 0 °C ... +30 °C. Storage temperature range –30 °C ... +70 °C.
Stakeless Earth/Ground Resistance Testing Principle of Operation Dimensions Total length of adaptercable 1,8 m, Length of shielded cable to clamp-on CT 1,5 m. Operating error*: ± (10% of m.v. + 5 digit). Display range*: 0,010 Ω ... 130 Ω. Measuring frequency: 128 Hz. Measuring voltage: Um=48 VAC (primary). Measuring range*: 0,020 Ω ... 100 Ω. Resolution: .001... .1 ohm. *when using: CT EI-162AC to induce voltage and CT EI-162X to detect current. Recommended distance between CT's: 10 cm.
1625 Users Manual Equivalent diagram AC Source U RX R1 R2 R3 Rn-1 Rn edw061.
Stakeless Earth/Ground Resistance Testing Principle of Operation If the parallel connection of resistors, R1...Rn is considerably lower than the ground connection under test RX: 1 1 + 1 R R 1 then R X + ⋅⋅⋅⋅ 2 = << R X 1 R n U is a reasonable approximation. I The test voltage (U) is applied without disconnecting ground rod and/or the direct electrical connection by means of a clamp-on current transformer and the current detected by a second current transformer.
1625 Users Manual Operation Connect the adapter according to the diagram and the designations E, S and H (C1, P1 and P2 for US-version) to the tester and to a current clamp. H 1625 EARTH / GROUND TESTER START TEST H/C2 S DISPLAY MENU Black S/P2 Earth/Ground Resistance 300k RA AC Resistance 300 k DC Low Resistance 3k R R 2 POLE 4 POLE 3 POLE 4 POLE CHANGE ITEM 3 POLE 2 POLE SELECT EI-162AC 4 POLE ES/P1 E OFF E /C1 Red EI-162X edw063.
Stakeless Earth/Ground Resistance Testing Principle of Operation Erder >10 cm edw064.eps Pushing the START-button will display the value of RE. Note In this particular mode the values of RH and RS have no meaning. Settings on the Tester Refer to the Operation section in the Testers instruction manual. The rotary switch of the tester must be in the RE 3 pole position.
1625 Users Manual Applications Example1: Ground rod on power poles. edw065.eps Example 2: Tests on multi-grounded (inter-connected) systems: Ground conductors are for example bonded to grids or concrete-footing grounds and other conducting elements such as lightning protection systems or frameworks. In this case the resistances of individual ground paths are not of significance. It must be tested if the resistance of the bonding is sufficiently low and reliable.
Stakeless Earth/Ground Resistance Testing Principle of Operation Lightning Protection M Footing ground Framework edw066.
1625 Users Manual Description of Displays With stakeless ground testing some display combinations have certain significance. Display Significance Polarity of CT’s is reversed Note Turn one CT E edw067.eps Switch Resistance under test is on/off for below meas- next test uring range or adapter cable is plugged into ground tester incorrectly edw068.
Stakeless Earth/Ground Resistance Testing Principle of Operation Display ST Significance V Note Resistance under test is above measuring range edw069.
Appendix B Earthing Resistance Introduction Per definition, the earthing resistance consists of several individual resistances. 1. The resistance of connecting lead to earth electrode 2. The resistance of the actual earth electrode; earthing rod, earthing plate, earthing strip, mesh earth electrode etc. 3. The dissipation resistance, the resistance between earth electrode and soil potential.
Earthing Resistance Principle of Operation Type of Soil Soil Resitivity Earthing Resistance (Ω) Earthing Rod m Depth [ρE] Earthing Strip m Ω.
1625 Users Manual Soil Resistivity ρE The soil resistivity is the resistance measured between two opposing surfaces of a cube of homogenous soil material with a lateral length of 1 meter. The unit is Ωm (see picture) 2 A=1m p = A . R( E L m) L=1 m edw054.eps The soil resistivity significantly depends on the specific kind of material (farming soil, dry sand, moist sand, concrete, gravel etc.), but also depends on seasonal changes.
Earthing Resistance Principle of Operation 28 Earth resistance RE 24 20 16 12 8 4 0 0 1 2 3 4 5 6 7 9 8 10 July Jan. 11 12 Dec. month edw055.eps Temporal change of the earthing resistance of a conductor earth electrode (earth strip, earth cable). 14 Earth resistance RE 12 10 8 6 4 2 0 0 1 Jan. 2 3 4 5 6 July 7 8 9 10 11 12 Dec. month edw056.
1625 Users Manual Measuring Method The current voltage measuring method is based on the block diagram circuit shown in the figure below. U meas. G I V E ES E RE I H S S RS H RH UE edw057.eps An AC generator G feeds current I via earth electrode E (earth electrode resistance RE) and auxiliary earth electrode H (auxiliary earth electrode resistance RH). Voltage UE drops on earthing resistance RE (UE proportional to RE.) This voltage is picked up and measured by probe S.
Earthing Resistance Principle of Operation The Potential Gradient Area Around every earth electrode a so called potential gradient area develops during the flow of an electric current (see picture below). U UE US E 40 60 m edw058.eps If the voltage between the earth electrode and a probe with a distance "a" from the earth electrode is measured, the value increases less with increasing distance.
1625 Users Manual The Influence of Potential Gradient Areas on Earth Resistance Measurement To pick off the true voltage drop from the earthing resistance (= the resistance between the earth electrode and the soil potential FE) it is to be assured that the probe is set outside the potential gradient area of all connected earth electrodes and the auxiliary earth electrode H. UG I G I I1 E1 V US1 S1 US1 V I2 E2 US2 V S2 US2 US4 H S4 S3 US3 US4 US2 FE V UG edw059.
Earthing Resistance Principle of Operation Earth Impedance (R*) on High Voltage Transmission Lines The earthings of transmission line pylons are interconnected via the overhead earth wire. This wire is not only ohmic. There is also inductivity and resistivity (L´, R´). For calculation of the short circuit current this impedance at line frequency has to be determined. Inductivity and resistivity are known in most cases.
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