Heating and D.h.w. Controller RVL481 Basic Documentation Edition: 1.0 Controller series: A CE1P2541en 20.05.
Siemens Switzerland Ltd Building Technologies Group International Headquarters Gubelstrasse 22 CH – 6301 Zug Tel. +41 41 724 24 24 Fax +41 41 724 35 22 www.sbt.siemens.com © 2008 Siemens Switzerland Ltd Subject to alteration 2/118 Siemens Building Technologies Heating and D.h.w. Controller RVL481 CE1P2541en 20.05.
Contents 1 Summary ...................................................................................................... 11 1.1 Brief description and key features ................................................................. 11 1.2 Equipment combinations ............................................................................... 11 1.2.1 Suitable sensors ............................................................................................ 11 1.2.2 Suitable room units................
.1.3 Room model...................................................................................................25 4.2 Flow and boiler temperature (B1) ..................................................................25 4.2.1 Measurement .................................................................................................25 4.2.2 Handling faults ...............................................................................................26 4.3 Outside temperature (B9) ............
8.1 Operating line ................................................................................................ 34 8.2 General.......................................................................................................... 34 9 Function block "Cascade slave"................................................................ 35 9.1 Operating lines .............................................................................................. 35 9.2 Mode of operation........................
11.2.2 Setpoint rise ...................................................................................................48 11.3 3-position control............................................................................................48 11.4 Excess mixing valve or heat exchanger temperature ....................................49 11.5 Pulse lock.......................................................................................................49 12 Function block "Boiler".....................
16.1 Operating lines .............................................................................................. 62 16.2 Assignment of d.h.w. heating ........................................................................ 62 16.3 Program for the circulating pump .................................................................. 62 16.3.1 General mode of operation............................................................................ 62 16.3.
20.1 Operating lines...............................................................................................75 20.2 Function .........................................................................................................75 20.2.1 Flow temperature boost .................................................................................75 20.2.2 D.h.w temperature control..............................................................................75 20.3 Pulse lock.....................
25.3.2 Relay test....................................................................................................... 84 25.3.3 Sensor test .................................................................................................... 85 25.3.4 Test of H–contacts......................................................................................... 86 25.4 Auxiliary functions.......................................................................................... 86 25.4.
28.2 Combination with SYNERGYR central unit OZW30 ....................................103 28.3 Communication with other devices ..............................................................103 29 Handling......................................................................................................104 29.1 Operation .....................................................................................................104 29.1.1 General .........................................................
1 Summary 1.1 Brief description and key features • The RVL481 is a multifunctional heating controller for use in residential and nonresidential buildings that have their own d.h.w. heating facility • Suited for: − Heating zone control with or without room influence via weather-compensated flow temperature control − Precontrol via demand-compensated control of the main / secondary flow temperature − Precontrol via demand-compensated boiler temperature control.
1.2.2 Suitable room units • Room unit QAW50 • Room unit QAW70 1.2.3 Suitable actuators All types of actuators from Siemens with the following features can be used: • Electromotoric or electrohydraulic actuators with a running time of 0.5…14.5 minutes • 3-position control • Operating voltage AC 24… 230 V 1.2.4 Communication Communication is possible with the following units: • All LPB-compatible controllers supplied by Siemens • SYNERGYR central unit OZW30 (software version 3.
2 Use 2.1 Types of plant The RVL481 is suitable for all types of heating plant that use weather-compensated flow temperature control. In addition, it can be used for demand-compensated control of the main flow. With regard to d.h.w. heating, the RVL481 is suited for plants with storage tanks or d.h.w. heating via heat exchangers (instantaneous d.h.w. heating) or via solar collector. Main applications: • Heating zones and d.h.w. heating with own heat generation • Heating zones and d.h.w.
• • • • • • • • • • • • • • • • • Input of 8 holiday periods per year Automatic summer- / wintertime changeover Display of parameters, actual values, operating state and error messages Communication with other units via LPB Remote operation via room unit and external switches Service functions Frost protection for the plant, the boiler and the house or building Minimum or maximum limitation of the return temperature DRT limitation Minimum and maximum limitation of the flow temperature Maximum limitation of
3 Fundamentals 3.1 Key technical features The RVL481 offers 2 key technical features: • The RVL481 has 6 heating circuit plant types and 5 d.h.w. plant types preprogrammed. When making use of all possible or practical combinations, there is a total of 29 plant types available • All functions and their settings are combined in the form of function blocks 3.1.
• Function block “Derivative action time d.h.w. heating via heat exchanger” • Function block “Multifunctional relay” • Function block “Legionella function" • Function block "Switching program 3" • Function block “Service functions and general settings” • Function block “Solar d.h.w. heating“ • Function block “Locking functions” For each function block, the required settings are available in the form of operating lines.
Notes on the plant diagrams with the different types of space heating and d.h.w. circuits are given in the following sections: and indicate where and how the space heating circuit is connected to • Symbols the d.h.w. circuit. where: representing the flow representing the return • The numbers beneath these symbols indicate the type of d.h.w. circuit with which the heating circuit can be combined 3.2.
Heating circuit plant type 3 Heating circuit control with heat exchanger Space heating with district heat connection, with weather-compensated flow temperature control acting on the valve in the primary return of the district heat connection. Outside temperature signal from own sensor or data bus. With or without room influence. Heating up and setback according to the heating program. Can be combined with d.h.w.
Heating circuit plant type 6 Precontrol with heat exchanger Precontrol with district heat connection, with demand-compensated control of the secondary flow temperature acting on the valve in the primary return. Heat demand signal from data bus. No heating program. Can be combined with d.h.w. types: • with types 1 and 2 via hydraulic connection at • with type 5 without hydraulic connection and N1 2541S06 Y1 B7 B71 1, 2 3.2.3 D.h.w. plant types Legend for sections 3.2.2 and 3.2.
D.h.w. heating with mixing group Charging of d.h.w. storage tank through control of the mixing valve according to own temperature sensor in the storage tank flow. Acquisition of the d.h.w. temperature with one or 2 sensors or thermostats. Circulating pump and solar collector or electric immersion heater are optional. 2542S02 D.h.w. plant type 2 N1 Y7 B3 B6 B31 M4 M3 K6 B32 M5 D.h.w. heating with changeover valve Charging of the d.h.w. storage tank through control of the changeover valve.
Siemens Building Technologies Heating and D.h.w. Controller RVL481 3 Fundamentals Solar d.h.w. heating Service functions and general settings Time switch program 3 Derivative action time d.h.w.heating via heat exchanger Multifunctional relay Legionella function D.h.w. storage tank 3-position d.h.w. actuator D.h.w. priority and flow temperature setpoint Basic settings d.h.w. Release of d.h.w. charging Max. limitation of d.h.w.
3.4 Heating circuit operating modes The heating circuit operating mode is selected on the controller by pressing the respective button. Also, the operating mode can be changed by bridging terminals H1–M. 3.4.
3.6 Manual operation The RVL481 can be switched to manual operation. In this case, the control will be switched off. In manual operation, the various actuating devices behave as follows: • Heating circuit mixing valve: This mixing valve is not under voltage, but can be manually driven to any position by pressing the manual buttons / (close) and / (open). The heating circuit pump / circulating pump is continuously running. • Boiler: The 2 burner stages are continuously on.
3.8 Operating state and operational level The user selects the required heating circuit operating mode by pressing the respective button. Each operating state has a maximum of 2 operating states – with the exception of operating mode "Continuously NORMAL heating" (only one operating state possible). When the ECO function is active, and in the case of quick setback, the operating state is always OFF.
4 Acquisition of measured values 4.1 Room temperature (A6, B5) 4.1.1 Measurement The following choices exist: • A room temperature sensor QAA24 can be connected to terminal B5 • A room unit QAW50 or QAW70 can be connected to terminal A6 • 2 units can be connected to the terminals. In this case, the RVL481 can ascertain the average of the 2 measurements. The other room unit functions will not be affected by averaging 4.1.
4.2.2 Handling faults A short-circuit or open-circuit in the measuring circuit is identified and indicated as a fault. In that case, the plant responds as follows: • Plants with 3-position control: Heating circuit pump / circulating pump M1 continues to run and the mixing valve will close • Plants with 2-position control: The heating circuit pump / circulating pump M1 continues to run and the burner will shut down 4.3 Outside temperature (B9) 4.3.
4.4.2 Handling faults If there is a short-circuit or open-circuit in the measuring circuit, and if the controller requires the return temperature, it responds as follows: • If there is a return temperature from a controller of the same segment available on the data bus, it is used (only with plant type 1–x).
4.7.2 Handling faults The controller's response to faults in the measuring circuits depends on the type of d.h.w. demand (setting on operating line 126): • One d.h.w. storage tank temperature sensor (operating line 126 = 0 or 4): In the event of a short-circuit or open-circuit in one of the 2 measuring circuits, the controller continues to work with the other measuring circuit, if possible. An error message will not be generated.
5 Function block "Enduser space heating" This function block contains settings that the enduser himself can make. 5.
5.4 Holiday program A maximum of 8 holiday periods per year can be programmed. At 00:00 of the first day of the holiday period, changeover to the setpoint for frost protection / holiday mode takes place. At 24:00 of the last day of the holiday period, the RVL481 will change to NORMAL or REDUCED heating in accordance with the time switch settings. The settings of each holiday period will be cleared as soon as the respective period has elapsed. Holiday periods may overlap.
6 Function block "Enduser d.h.w." This function block contains settings for d.h.w. heating that the enduser himself can make. 6.1 Line Operating lines Function, parameter 26 Setpoint of NORMAL d.h.w. temperature 27 D.h.w. temperature 28 Setpoint of REDUCED d.h.w. temperature 6.2 Factory setting (Range) Unit 55 (20…100) °C Display function 40 (8…80) °C Setpoint The NORMAL and REDUCED d.h.w. temperature setpoints are to be entered in °C.
7 Function block "Enduser general" This function block contains settings that the enduser himself can make, as well as indication of faults. 7.1 Line 31 32 33 34 35 36 37 38 39 40 41 50 7.
7.4 Indication of errors The following errors are indicated: Number 10 Fault Fault outside sensor 30 Fault flow temperature sensor 40 Fault return temperature sensor (primary circuit) 42 Fault return temperature sensor (secondary circuit) 50 Fault storage tank temperature sensor/control thermostat 1 52 Fault storage tank temperature sensor/control thermostat 2 54 Fault d.h.w.
8 Function block "Plant type" This function block only contains the selection of the plant type. 8.1 Line 51 8.2 Operating line Function, parameter Factory setting (range) Plant type Unit 1−1 (1−0…6−5) General When commissioning the plant, the respective plant type must be entered first. This ensures that the functions required for the specific type of plant, the parameters and operating lines for the settings and displays will be activated.
9 Function block "Cascade slave" This function block facilitates integration of the controller as a cascade slave into a heat source cascade. A heat source cascade is the combined operation of several oil- / gasfired boilers. 9.1 Line 59 60 Operating lines Function, parameter Release integral for boiler sequence Reset integral of boiler sequence 9.
10 Function block "Space heating" This function block performs the ECO function, the optimization functions with boost heating and quick setback, as well as the room influence. 10.
circumstances, the heating would be switched on because the outside temperature drops for a few days TA (B9 rsp.
Switching the heating on The heating will be switched on again only when all 3 of the following conditions are satisfied: • The actual outside temperature has fallen 1 °C below the current ECO heating limit • The composite outside temperature has fallen 1 °C below the current ECO heating limit • The attenuated outside temperature has fallen 1 °C below the "ECO day" heating limit 10.2.
To perform the optimization function, the controller makes use of the actual room temperature – acquired by a room temperature sensor or room unit – or the room model. With room sensor Using a room sensor or room unit, it is possible to have optimum start and optimum stop control. To be able to optimally determine the switch-on and switch-off points, optimization needs to "know" the building's heating up and cooling down characteristics, always as a function of the prevailing outside temperature.
TR TRw TRM 2540D02 TRw TRw t1 t Progression of room temperature generated by the room model e kt t t1 TAM TR TRM TRw TRw 2.71828 (basis of natural logarithms) Building time constant in hours Time in hours Quick setback Composite outside temperature Room temperature Room model temperature Setpoint of NORMAL room temperature Setpoint of REDUCED room temperature 10.4.5 Optimum stop control During the building's occupancy time, the RVL481 maintains the setpoint of NORMAL heating.
10.4.7 Optimum start control During the building's non-occupancy times, the RVL481 maintains the setpoint of REDUCED heating. Toward the end of the non-occupancy time, optimization switches the control to boost heating. This means that the selected boost will be added to the room temperature setpoint. Optimization calculates the changeover time such that, at the start of occupancy, the room temperature will have reached the setpoint of NORMAL heating.
TR TRw TRw TRw TRM 2540D04 TRM1 TRw t1 kt t t1 TR TRw TRw TRM TRM1 TRw ∆TRw t Building time constant in hours Time Duration of room temperature setpoint boost with boost heating Room temperature Setpoint of NORMAL room temperature Setpoint of REDUCED room temperature Room model temperature Room model temperature at the beginning of boost heating Room temperature setpoint Boost of room temperature setpoint (with boost heating) 10.5 Room functions 10.5.
10.5.2 Room influence The room temperature is included in the control process. For that purpose, a room sensor is required (sensor or room unit). The gain factor of the room temperature influence on the flow temperature control can be adjusted.
Setting with the bar 2540Z09 Setting on the operating lines The setting is to be made on operating lines 14 and 15. Operating line 14 15 Selection of setting Setpoint TV1, current flow temperature setpoint at an outside temperature of 15 °C TV2, current flow temperature setpoint at an outside temperature of –5 °C The type of setting is to be entered on operating line 73.
10.6.4 Parallel displacement of heating curve The heating curve can be displaced parallel: • Manually with the setting knob for room temperature readjustments. The readjustment can be made by the enduser and covers a maximum range of −4.5…+4.
10.7 Generation of setpoint 10.7.1 Weather-compensated control SYNERGYR OZW30 Setting knob room unit* 2540B01 Weather-compensated control is used with plant types 1−x, 2−x and 3−x. The setpoint is generated via the heating curve as a function of the outside temperature. The temperature used is the composite outside temperature.
11 Function block "3-position actuator heating circuit" This function block provides 3-position control of the heating circuit.
11.2.2 Function Setpoint rise TVw TVw ∆TVw ∆t 2540D07 t Maximum rise: = t t ∆t TVw ∆TVw Time Unit of time Flow temperature setpoint Rate of setpoint increase per unit of time The rate of increase of the flow temperature setpoint can be limited to a maximum. In that case, the maximum rate of increase of the flow temperature setpoint is the selected temperature per unit of time (°C per hour).
11.4 Excess mixing valve or heat exchanger temperature Example interconnected plant wN2 + w wN1 = wN2 + w wN2 BUS (LPB) 2540S07 In interconnected plants, an excess mixing valve or heat exchanger temperature can be entered on the RVL481. This is a boost of the respective heating zone's flow temperature setpoint. The higher setpoint is delivered to the heat source as the heat demand signal.
12 Function block "Boiler" Function block "Boiler" acts as a 2-position controller and is used for direct burner control. Depending on the type of plant, it acts as a: • boiler temperature controller for weather-compensated control of a space heating system (plant type 2–x) • boiler temperature controller for demand-compensated control of a main flow (plant type 5–x) 12.
12.3.2 Minimum limitation of the boiler temperature For minimum limitation of the boiler temperature, the minimum limit value can be adjusted. The switch-on point cannot fall below the minimum limit value. The switch-off point will then be higher by the amount of the set switching differential If the return temperature is limited, the display shows . 12.3.3 Actions during d.h.w. heating Both the maximum and the minimum limitation also act during d.h.w. heating. 12.
12.4.2 Setting parameters Control with a 2-stage burner For 2-position control with a 2-stage burner, the variables that can be set are the switching differential and the minimum burner running time – which now apply to both stages – plus the following variables: • The release integral (FGI) for the second stage. This is the variable generated from the temperature (T) and time (t).
TKx TKw + 0,5 * SD TKw - 0,5 * SD t YB1 1 0 t INT max. max. 0 FGI RSI RSI t FGB2 1 0 t 2522D09 YB2 1 0 t FGB2 FGI INT RSI SD t TKw TKx YB1 YB2 Release of burner stage 2 Release integral Integral Reset integral Switching differential Time Boiler temperature setpoint Actual value of boiler temperature Control signal for burner stage 1 Control signal for burner stage 2 12.4.
12.4.4 Protective boiler startup If the boiler temperature falls below the minimum limit of the boiler temperature while the burner is running, the differential (minimum limit value minus actual value) will be integrated. From this, a critical locking signal will be generated and transmitted to the connected loads. This causes the loads to reduce their setpoints, thus consuming less energy. If the critical locking signal exceeds a defined value, the boiler pump will be deactivated also.
12.4.5 Protection against boiler overtemperatures To prevent heat from building up in the boilers (protection against overtemperatures), the RVL481 offers a protective function. When the first burner stage is switched off, the controller allows pump M1 to overrun for the set pump overrun time (operating line 174 on the boiler temperature controller), generating at the same time a forced signal to all loads (inside the controller on the data bus).
13 Function block "Setpoint of return temperature limitation" On the function block "Setpoint of return temperature limitation”, the setpoint of minimum limitation of the return temperature or the constant value for shifting maximum limitation of the return temperature can be adjusted. 13.1 Operating line Line Function, parameter 101 Setpoint of return temperature limitation – Constant value 13.
Mode of operation with a single device (with no bus) 2524B03e 13.3.3 Controller 1 Boiler controller With no possibility of minimum return temperature limitation 13.3.
14 Function block "District heat" Together with function block "3-position actuator heating circuit", this function block provides flow temperature control in plants with an indirect (heat exchanger) or direct district heat connection.
TPR 90 80 70 TL constant 60 s 50 40 TL start 2381D03 30 20 TA 30 s TA TL constant TL start TPR Function 20 10 0 Slope of limitation (operating line 112) Actual outside temperature Constant value of limitation (operating line 101) Start of shifting limitation (operating line 113) Primary return temperature -10 . The outside temperature is used as a compensating variable for maximum limitation of the primary return temperature. It can be delivered either by the local sensor or the LPB.
Example of the effect of maximum limitation of the return temperature differential: VS DRTOFF DRTon VP [%] 2540D11 100 90 80 70 60 50 40 30 20 10 0 t DRTOn DRTOFF t VS 14.2.
15 Function block "Maximum limitation of the return temperature, d.h.w." In plants with district heat connection, function block “Maximum limitation of the return temperature, d.h.w.” provides maximum limitation of the primary return temperature during d.h.w. heating. Since for that purpose, the primary return temperature must be acquired during d.h.w. heating, this function can only be implemented with plant types where d.h.w.
16 Function block "Basic settings d.h.w." Function block "Basic settings d.h.w." is used to select the heating circuits for which the d.h.w. is heated and according to which program the d.h.w. circulating pump shall operate. 16.1 Operating lines Line Function, parameter 121 Assignment of d.h.w. heating 0 (0…2) 122 Program for the circulating pump 2 (0…3) 16.2 Factory setting (range) Unit Assignment of d.h.w. heating Operating line 121 is used to select for which heating circuits the d.h.w.
vides heating to the NORMAL temperature according to its heating program (independent of the operating mode) and is not in holiday mode. The circulating pump runs with a forward shift against the times of the heating program; this means it is affected by optimum start control. With plant types 4–x, 5–x, and 6–x and the setting of “0” (own controller) on operating line 121, the circulating pump never runs since these plant types have no own heating program.
16.4 Frost protection for d.h.w. The frost protection for d.h.w. provided by the RVL481 is ensured by sensors B3, B31 and B32. The behavior depends on the type of plant. 16.4.1 Frost protection in the d.h.w. storage tank This type of frost protection is used with plant types x–1, x–2, and x–3. It always ensures a minimum switch-on temperature of 5 °C.
17 Function block "Release of d.h.w. heating" Based on the settings made, function block "Release of d.h.w. heating" determines at what times d.h.w. heating will be released to the NORMAL d.h.w. setpoint. 17.1 Operating line Line Function, parameter 123 Release of d.h.w. heating 17.2 Release 17.2.1 Function Factory setting (range) Unit 2 (0…2) 25 41 B03 en On operating line 123, it is possible to select at what times d.h.w. heating is to be released to the NORMAL d.h.w. setpoint.
17.2.2 Release programs Depending on the setting made on operating line 123, release of d.h.w. heating takes place at the following times: Setting D.h.w. heating is released 0 1 2 Continuously (24 hours a day) According to one or several heating programs According to switching program 2 of own controller With setting 1, d.h.w release depends on the setting made on operating line 121.
18 Function block "D.h.w. priority and flow temperature setpoint" On this function block, the kind of d.h.w. priority (absolute, shifting, or parallel) and the generation of the common flow temperature setpoint (maximum selection, d.h.w.) are set. 18.1 Operating line Line Function, parameter 124 D.h.w. priority, flow temperature setpoint 18.2 Factory setting (range) Settings Operating line 124 D.h.w.
18.3.2 Shifting priority During d.h.w. charging, the heating circuits will be throttled if the heat generating equipment (the boiler) is not able to maintain the required setpoint. In that case, the display of the boiler controller shows . • Controller with no bus connection: If, during d.h.w.
Example It is assumed that the mixing heating circuit calls for 80 °C and the d.h.w. circuit for 65 °C. With d.h.w. charging, the setpoint of the common flow temperature will then be that of the d.h.w. circuit, namely 65 °C. 69/118 Siemens Building Technologies Heating and D.h.w. Controller RVL481 18 Function block "D.h.w. priority and flow temperature setpoint" CE1P2541en 20.05.
19 Function block "D.h.w. storage tank" Based on the settings made, this function block performs all d.h.w. functions required for the plant types with a d.h.w. storage tank. With plant types x–5 (electric immersion heater only ), this function block is not active (except operating line 126) since the electric immersion heater provides the functions independent of the RVL481. The settings for solar d.h.w.
19.3 D.h.w. temperature and d.h.w. switching differential The kind of d.h.w. storage tank temperature acquisition must be entered on operating line 126. In plant types x–5 without solar heating, select setting 0, 1, 2 or 3 on operating line 126, although d.h.w. heating with electric immersion heater does not require either sensor or thermostat. The storage temperature can be acquired via • 1 or 2 sensors • 1 or 2 thermostats • 1 or 2 sensors with solar function; this activates function "Solar d.h.w.
19.4 Boost of the d.h.w. charging temperature The boost of the d.h.w. charging temperature in °C can be set on operating line 127. The boost refers to the setpoint of the d.h.w. temperature. The lower the setting of this value, the longer d.h.w. charging takes. TLw = TBWw + TBW∆ [°C] Example Setpoint of d.h.w. temperature (TBWw, operating line 26) = 50 °C Boost of the d.h.w.
19.7 Forced charging On operating line 131, it is possible to select whether or not forced charging of the d.h.w. storage tank shall take place daily when d.h.w. heating is released for the first time. With forced charging, the d.h.w. storage tank will also be charged when the d.h.w. temperature lies between the switch-on and the switch-off temperature. The switch-off point remains the same. If d.h.w. heating is released 24 hours a day, forced charging takes place every day at midnight.
19.9 Manual d.h.w. charging D.h.w. charging can be initiated manually by pressing the d.h.w. button for 5 seconds. As a confirmation, the button will flash for 5 seconds. Manual d.h.w. charging is active also when • d.h.w. heating is not released • the d.h.w. temperature lies inside the switching differential • d.h.w. heating is switched off • d.h.w. heating is switched off due to holiday mode • d.h.w.
20 Function block "3-position actuator for d.h.w." With plant types x–2 and x–4, this function block provides 3-position control of d.h.w. heating. 20.1 Operating lines Line Function, parameter 132 Flow temperature boost mixing valve / heat exchanger Factory setting (range) Unit 10 (0…50) 133 °C Actuator opening time 120 (10…873) s 134 Actuator closing time 120 (10…873) s 135 P-band of control (Xp) 32.0 (1…100) °C 136 Integral action time of control (Tn) 120 (10…873) s 20.
21 Function block "Derivative action time d.h.w. heating via heat exchanger" With plant types x–4, this function block permits entry of the D-part with d.h.w. control. 21.1 Operating line Line Function, parameter 137 Derivative action time of control (Tv) 21.2 Factory setting (range) Unit 16 (0…255) s Description The 3-position controller provides PID mode. The derivative action time Tv (D-part) can be set on operating line 137.
22 Function block "Multi-functional relay" The RVL481 features a multifunctional relay whose function is selected on this block. This relay is also used for controlling an electric immersion heater for d.h.w. heating. This means that if the parameters of the controller are set to "Electric heater for d.h.w. only" (plant type x–5) or changeover operation, the relay cannot used for any other functions. The settings on that block are then inactive. 22.
22.2.3 ON / OFF according to the time switch The multifunctional relay is energized and deenergized according to the time switch entered on operating line 146. With the plant types that do not have their own heating circuit ( 4–x, 5–x, and 6–x), the setting "According to the heating program" makes no sense, since these types of plant have no heating program. In that case, the multifunctional relay is always de-energized. 22.2.
23 Function block "Legionella function" In the case of d.h.w. heating systems with storage tanks, this function prevents the formation of legionella bacteria. This is accomplished by periodically heating the d.h.w. to a certain temperature level. 23.1 Operating lines Line Function, parameter 147 148 149 150 Periodicity of the legionella function Time of legionella function Dwelling time at legionella setpoint Circulating pump operation during the legionella function 23.1.
23.2 Mode of operation Preconditions for the legionella function: • The d.h.w. storage tank temperature is acquired with one or 2 sensors (the legionella function is not possible with thermostats) • Charging takes place instantaneously with the heating water and not with the electric immersion heater • A legionella setpoint is adjusted • D.h.w.
24 Function block "Switching program 3" Switching program 3 of this function block can be used for one or several of the following functions: • As a time switch program for the circulating pump (operating line 122) • As a time switch program for the multifunctional relay (operating lines 141 and 146) 24.
25 Function block "Service functions and general settings" Function block "Service functions and general settings" is used to combine various displays and setting functions that are of assistance in connection with commissioning and service work. In addition, a number of extra functions are performed. The service functions are independent of the type of plant. 25.
Generation of the flow temperature setpoint Parallel displacement of heating curve, operating line 72 Heating curve 1+s TV TAM TVS TVS TVw s TAM Flow temperature setpoint, operating line 165 2541B04e 1+s Setting knob on controller s TAM TVS TVw Slope Composite outside temperature Flow temperature setpoint (generated via the heating curve) Flow temperature setpoint 25.2.
25.2.4 Software version The controller displays the software version in use. 25.2.5 Identification number of room unit Based on the number shown in the display, the type of room unit used can be identified. The types of room units that can currently be used with the RVL472 carry the following numbers: 82 = QAW50 83 = QAW70 The RVL481 ignores room units that cannot be used (e.g. QAW20) and generates an error message (error code 62). 25.3 Commissioning aids 25.3.
There are 4 choices to terminate the relay test: • Entry of 0 on the operating line • Leaving the setting level by pressing button or • Leaving the setting level by pressing the Info button or any of the operating mode buttons • Automatically after 30 minutes 25.3.3 Sensor test The connected sensors can be checked on operating line 163. In addition, if available, the current setpoints and limit values are displayed.
25.3.4 Test of H–contacts The connected H–contacts can be checked on operating line 164. It is always the current status that is indicated (contact open, contact closed). The contacts can be individually selected by pressing and . Input Contact H1 Overriding the operating mode (contact H1) H3 Operating lock (contact H3) H4 Minimum limitation of stroke (contact H4) The contact's status is displayed as follows: = contact closed = contact open 25.4 Auxiliary functions 25.4.
The display shows the fault status message with . More detailed information is given on operating line 50 under error code 120. The flow alarm can be deactivated by entering --:--.
D.h.w. discharging protection has priority over pump overrun. In interconnected plants, the time set also affects the forced signals that a boiler can deliver to ensure overtemperature protection. For detailed information, refer to section “12.4.5 Protection against boiler overtemperatures”. 25.4.5 Pump kick To prevent pump seizing during longer off periods (e.g.
Critical locking signals Critical locking signals are generated by the boiler temperature controller during protective boiler startup and during minimum limitation of the boiler return temperature. If the boiler temperature controller is located in segment 0, the critical locking signal will be sent to all loads and heat exchangers in the bus network and – if present – to its own heating and d.h.w. circuit.
25.5.2 Outside temperature source If, in interconnected plants, the outside temperature is delivered via the bus, the temperature source can be addressed either automatically or directly (operating line 180). • Automatic addressing: Display, entry Explanation SET A (For automatic addressing) ACTUAL xx.yy Display of source address selected by automatic addressing: xx = segment number yy = device number • Direct addressing: To be entered is the source address: xx.
25.5.4 Bus power supply In interconnected plants with a maximum of 16 controllers, the bus power supply may be decentralized, that is, power may be supplied via each connected device. If a plant contains more than 16 devices, a central bus power supply is mandatory. On each connected device, it is then necessary to set whether the data bus is powered centrally or decentrally by each controller. With the RVL481, this setting is made on operating line 179.
26 Function block "D.h.w. solar charging" The RVL481 supports solar d.h.w. heating with the d.h.w. plant types 1, 2, 3 and 5. The function is activated on operating line 126 by selecting the d.h.w. temperature sensor. This always enables solar d.h.w. charging, carried out via the collector pump based on the temperature differential between d.h.w. storage tank and collector temperature. The lower storage tank sensor B32 is used for solar charging control.
2541D14 T TKol SDON SDOFF TSp TLmin ON OFF t TKol ON/OFF SDON SDOFF TSp TLmin T t Collector temperature Collector pump Temperature differential ON Temperature differential OFF Storage tank temperature Minimum charging temperature Temperature Time • The storage tank is charged if the collector temperature exceeds the current storage temperature by the switch-on differential: TKol > TSp + SDON • Storage tank charging is stopped if the collector temperature drops below the temperature differential: TKol
26.2.3 Minimum runtime 2541D07 When the collector pump is switched on, it remains on for min. runtime tMin = 20 s. This minimum runtime is enabled for all functions activating the collector pump. tMin fSolar ON OFF t fSolar ON/OFF tMin Collector pump switch-off is delayed by the minimum runtime after the frost protection limit is reached to rinse the flow pipe between collector to storage tank with hot water.
26.2.5 Collector temperature to protect against overheating 2541D15 Operating line 204 allows for setting the temperature protecting the collector against overheating. If there is a risk of overheating at the collector, storage tank charging is continued past the charging temperature maximum limitation (set on operating line 206) to the storage tank temperature maximum (set on operating line 207) to reduce the amount of surplus heat.
SDON TRk 2541D10 T TSp 2K 1K 1K TKol ON OFF t SDON TRk TSp TKol Temperature differential ON Recooling setpoint Storage tank temperature Collector temperature ON/OFF Collector pump T Temperature t Time • The collector pump is switched on if the storage tank temperature is at least 2 K above the recooling setpoint and above the collector temperature by temperature differential ON.
26.2.8 Maximum limitation of charging temperature 2541D12 Operating line 206 allows for setting the maximum limitation for charging temperature. The collector pump is switched off if the maximum charging temperature in the storage tank is reached.
26.2.10 Collector start function gradient 2541D13 The pump must periodically be switched on, as the temperature at the collector (primarily vacuum pipes) cannot be measured reliably when the pump is off. Operating line 208 allows for setting the collector start gradient function. The pump is switched on if the collector temperature increases by less than the set gradient. The pump remains on if the required temperature increase at the collector is reached within one minute.
27 Function block "Locking functions" On the software side, all settings can be locked to prevent tampering. Also, the settings required for district heat applications can be locked on the hardware side. 27.1 Operating line Line Function, parameter 248 Locking of settings 27.2 Factory setting (range) Unit 0 (0…2) Locking the settings on the software side On operating line 248, the settings made on the controller can be locked on the software side.
28 Communication 28.1 Combination with room units 28.1.1 General • Room units can be used with the RVL481 only if one of the plant types 1–x, 2–x, or 3–x has been selected on the controller • The room temperature acquired by a room unit is adopted by the RVL481 at terminal A6. If the room temperature signal delivered by the room unit shall not be considered by the control functions, the respective source needs to be selected (operating line 65).
Knob for room temperature readjustments Using the knob of the QAW50, the room temperature setpoint of NORMAL heating can be readjusted by ±3 °C. The adjustment of the room temperature setpoint on the controller's operating line 1 will not be affected by the QAW50. 28.1.
Knob for room temperature readjustments With the knob of the QAW70, the room temperature setpoint of NORMAL heating can be readjusted by ±3 °C. The adjustment of the room temperature setpoint on the controller's operating line 1 will not be affected by the QAW70. Effect of individual QAW70 operating lines on the RVL481 If 1 (slave with no remote operation) is entered on operating line 178 ("Source of time of day") of the RVL481, the time of day on the QAW70 cannot be changed.
Overriding the QAW70 entries from the RVL481 If the RVL481 with a connected QAW70 is isolated from the mains network and then reconnected, the following parameters on the QAW70 will be overwritten with the settings made on the RVL481: • Time of day and weekday • Complete heating program • Room temperature setpoint of REDUCED heating • Room temperature setpoint of REDUCED heating • NORMAL d.h.w temperature setpoint This means that the RVL481 is always the data master. 28.
Handling 29.1 Operation 29.1.
Operating instructions The Operating Instructions are inserted in a holder at the rear of the cover. When in their proper place, the list of operating lines that can be selected by the enduser is visible. The Operating Instructions are designed for use by janitors and endusers. They also contain tips on energy savings and troubleshooting. 29.1.2 Analog operating elements Buttons for selecting the heating circuit's operating mode For the selection of the operating mode, there are 4 buttons available.
Buttons To select and readjust setting values, the procedure is the following: Buttons Procedure Line selection buttons Press button Setting buttons Effect Selection of the next lower operating line Press button Selection of the next higher operating line Press button Decrease of the displayed value Press button Increase of the displayed value The value set will be adopted: • when selecting the next operating line • by pressing the Info button • by pressing any of the operating mode buttons or m
29.2 Commissioning 29.2.1 Installation instructions The RVL481 is supplied with Installation Instructions which give a detailed description of installation, wiring and commissioning with functional checks and settings. They have been written for trained specialists. Each operating line has an empty field in which the selected value can be entered. The Installation Instructions should not be thrown away after use but kept together with the plant documentation. 29.2.
29.3.
30 Engineering 30.1 Connection terminals B3 Ux B31 B9 1 2 3 4 5 6 7 8 9 10 B7 11 B32 B5 12 13 14 15 B6 B71 16 17 18 19 20 M M N L 1 2 Q3 F1 Y1 F2 Y2 Q5 F3 Q1 /Y3 /F4 /K4 /F5 /K5 3 4 5 6 7 8 9 10 Q4 K6 F6 Y7 Y8 F7 11 12 13 14 15 16 17 18 19 20 2541Z08 N 30.1.
L B9 B1 B M B M A6 LPB D1 D2 B3 B M B7 B31 B M B32 S1 B M B M B5 B M 2541A01 Low-voltage side Connection diagrams DC 0...10 V 30.
31 Mechanical design 31.1 Basic design The controller is comprised of controller insert, which accommodates the electronics, the power section, the output relays and – on the front – all operating elements, and the base, which carries the connection terminals. The operating elements are located behind a lockable transparent cover. On the inner side of the cover, there is a holder in which the operating instructions can be inserted. All values are read in the display (LCD) featuring background lighting.
32 Technical data Power supply Rated operating voltage Frequency Power consumption (no external load) Supply line fusing AC 230 V (±10 %) 50 Hz max. 9 VA 10 A Output relays Switching capacity Switching current Y1/K4, Y2/K5, Q1, Y7, Y8 Switching current Q5, Q3/Y3, Q4, K6 Rated current of ignition transformer Switch-on current of ignition transformer AC 24…230 V AC 0.02…2 (2) A AC 0.02…1 (1) A max. 1 A (max. 30 s) max. 10 A (max.
Index changeover valve ......................................................72 2 2-position control....................................................... 51 2-position controller................................................... 50 3 3-position control....................................................... 48 charging temperature max limitation solar ................96 circulating pump ........................................................62 collector frost protection ................................
E ECO function .............................................................36 function block maximum limitation of the return temperature, d.h.w.................................................... 61 ECO heating limits.....................................................37 function block multifunctional relay........................... 76 economy button.................................................99, 100 function block plant type ...........................................
knob ........................................................................ 104 optimization ...............................................................38 optimum shutdown ....................................................40 L legionella function ..................................................... 78 line selection buttons .............................................. 104 locking....................................................................... 98 locking on the hardware side ............
room temperature......................................................25 storage tank recooling (solar) ................................... 94 room temperature deviation ......................................43 storage tank temperature ......................................... 27 room temperature sensor ..........................................25 storage tank temperature maximum limitation.......... 96 room temperature setpoint boost ..............................
/118 Siemens Building Technologies HVAC Products Heating and D.h.w. Controller RVL481 Index CE1P2541en 20.05.
Siemens Switzerland Ltd Building Technologies Group International Headquarters Gubelstrasse 22 CH – 6301 Zug Tel. +41 41 724 24 24 Fax +41 41 724 35 22 www.sbt.siemens.com © 2008 Siemens Switzerland Ltd Subject to alteration 118/118 Siemens Building Technologies HVAC Products Heating and D.h.w. Controller RVL481 CE1P2541en 20.05.
