RDF660MB/MM, RDF660MB Flush-mounted room thermostat with RS485 Modbus communications Basic Documentation A6V12114068_en--_c 2021-05-17 Smart Infrastructure
Table of Contents 1 About this document .................................................................................5 1.1 1.2 1.3 Revision history ...........................................................................................5 Reference documents..................................................................................5 Before you start ...........................................................................................5 1.3.1 Copyright ...................................
4.6.4 4.7 4-pipe fan coil unit ...................................................................... 35 4.6.5 Chilled/heated ceiling and radiator applications .......................... 36 4.6.6 Compressor applications ............................................................ 36 4.6.7 Setpoints and sequences ........................................................... 37 Control outputs ......................................................................................... 38 4.7.1 4.7.2 4.
About this document Revision history 1 1 About this document 1.1 Revision history Edition Date Changes Section 1 January 2021 First version. All 1.1 March 2021 ● ● Update Multifunctional input info Update communication object related info 4.9 4.12.1 2 May 2021 ● Update commissioning and display info 2.2, 3.2, 3.3, 4.1 3 May 2021 ● ● Add RDF660MB related info Add electric heater related info ● ● 2.1, 4.9, 4.11.1, 4.12, 4.13, 6 2.2, 4.4.1, 4.4.2, 4.4.3, 4.5.4, 4.6.1, 4.6.3, 4.6.5, 4.
1 About this document Target audience, prerequisites 1.3.3 Document user/request to the reader Before using products from Siemens Industry, Inc., it is important that you read the documents supplied with or ordered at the same time as the products (equipment, applications, tools, and so on) carefully and in full. We assume that persons using our products and documents are authorized and trained appropriately and have the technical knowledge required to use our products as intended.
Overview Types 2 2 Overview 2.1 Types Product no. RDF660MB/ MM RDF660MB Stock no. Operating voltage S55770T433 Control outputs On/Off Fan types 3-pos DC 0...10 V 3-speed DC 0...10 V Backlit LCD AC 230 V ✓ ✓ - - ✓ ✓ AC 230 V ✓ ✓ - - ✓ ✓ Input Suitable conduit box Basic Square or White round B1, S1 S55770T439 Basic X1, X2 Color Square or White round 2.
2 Overview Integration via Modbus ● ● ● ● ● ● ● ● ● ● ● – External room temperature sensor or return air temperature sensor – Automatic heating/cooling changeover sensor S1 input freely selectable for (RDF660MB/MM only): – Window contact – Presence detector – Hotel keycard 2 multifunctional inputs (X1 and X2), freely selectable for (RDF660MB only): – External room temperature sensor or return air temperature sensor (AI) – Automatic heating/cooling changeover sensor (AI) – Window contact (DI) – Dew poi
2 Overview Accessories 2.4 Accessories Description SSN Data sheet Changeover mounting kit (50 pcs / package) ARG86.3 N3009 Plastic mounting spacer for flushmounted thermostats to increase the headroom in the conduit box by 10 mm ARG70.3 N3009 Note: Order accessories separately. 2.5 Equipment combinations Type of unit Cable temperature or changeover sensor, cable length 2.5 m NTC (3 kΩ at 25 °C) On/Off actuators Data sheet *) QAH11.
2 Overview Equipment combinations 3-position actuators Type of unit Product no. Data sheet *) Electric actuator, 3-position (for radiator valves) SSA31.. 4893 Electric actuator, 3-position (for 2and 3-port valves/V..P45) SSC31 4895 Electric actuator, 3-position (for small valves 2.5 mm) SSP31.. 4864 Electric actuator, 3-position (for small valves 5.5 mm) SSB31.. 4891 Electric actuator, 3-position (for small valve 5 mm) SSD31.. 4861 Electric actuator, 3-position (for valves 5.
3 Notes Mounting and installation 3 Notes 3.1 Mounting and installation Mounting ● ● ● ● ● Wiring ● ● See Mounting Instructions A6V12060783 enclosed with the thermostat. Comply with local regulations to wire, protect and earth the thermostat. ● The device has no internal fuse for supply lines to fan and actuators. To avoid risk of fire and injury due to short-circuits, the AC 230 V mains supply line must have a circuit breaker with a rated current of no more than 10 A.
3 Notes Commissioning 3.2 Commissioning Applications The room thermostat is delivered with a fixed set of applications. Select and activate the relevant application during commissioning using one of the following tools: ● Local DIP switch and HMI ● Modbus commissioning tools Set the DIP switches before snapping the front panel onto the mounting plate, if you want to select an application via DIP switches.
Notes Operation 3 3.3 Operation The thermostats consist of 2 parts: ● Front panel with electronics, operating elements and built-in room temperature sensor. ● Mounting base with power electronics. The rear of the mounting base contains the screw terminals. The base fits on a square conduit box with 60 mm fixing centers. Slide the front panel in the mounting base and snap on. Operation and settings 1. Operating mode selector 2. Change fan operation 3.
3 Notes Operation Display 1. Operating mode Protection Comfort Economy 2. Displays room temperature, setpoints and control parameters Symbol indicates current room temperature 3. Fan mode Auto fan active Fan speed: low, medium, high 4. Indicates fault or reminder 5. Heating/cooling mode Cooling Heating Electrical heater active (RDF660MB only) 6. Condensation in room (dew point sensor active) 7.
Notes Disposal 3 3.4 Disposal The device is considered an electronic device for disposal in accordance with the European Guidelines and may not be disposed of as domestic garbage. ● Dispose of the device through channels provided for this purpose. ● Comply with all local and currently applicable laws and regulations. 3.
4 Functions Temperature control 4 Functions 4.1 Temperature control General note: Parameters Setting of the control parameters (P01, etc., mentioned throughout the document), see Control parameters [➙ 53]. Temperature control The thermostat acquires the room temperature via built-in sensor, external room temperature sensor (QAA32), external return air temperature sensor (QAH11.
4 Functions Operating modes 4.2 Operating modes The thermostat operating mode can be influenced in different ways (see Different ways to influence the operating mode [➙ 18]), e.g. operating mode button, window contact, Modbus, etc. Specific heating and cooling setpoints are assigned to each operating mode. The operating mode can be selected via Modbus. ● If a bus command is received via Modbus for either Comfort or Economy, the symbol of the selected operating mode is displayed.
4 Functions Operating modes 4.2.1 Different ways to influence the operating mode Priority of operating mode interventions Priority Different interventions can influence the operating mode. The following table shows the priorities of different interventions. A lower number means higher priority. Description Remark ① Commissioning In the parameter setting mode, you can always command an operating mode independent of all other settings or intervention via Modbus and local input.
4 Functions Room temperature setpoint P02 Without time schedule 3 Description ● ⇨ ● 4 ⇨ ● ● ⇨ Switching manually between 2 modes, Economy is not available (factory setting) Suited for hotel guest rooms or commercial buildings Switching manually between 3 modes Suited for homes and rooms where manual switching to Economy is desired The thermostat is forced into Protection when the window is open. The contact can be connected to multifunctional input S1/X1/X2. Set P38/P40 to 3.
4 Functions Room temperature setpoint Example 2-pipe heating OR cooling 4-pipe heating AND cooling Cooling setpoint adjustable: 18…25 °C Heating setpoint adjustable: 18…25 °C Cooling setpoint adjustable: 18…25 °C Heating setpoint adjustable: 18…25 °C P09 < P10 P09 ≥ P10 Cooling setpoint adjustable: 25…35 °C Heating setpoint adjustable: 5…21 °C Economy mode Use control parameters P11 and P12 to adjust Economy setpoints. The heating setpoint is 15 °C (factory setting), and cooling setpoint is 30 °C.
Functions Room temperature setpoint 4 Only required for heating and cooling applications (see Setpoints and sequences [➙ 37]) 1) The current setpoint (used by the thermostat for temperature control) is available on the Modbus for use in the central control unit. Room temperature: Current setpoint General notes: ● ● Notes on setpoint adjustment ● ● A6V12114068_en--_c Changes via the local HMI or tool have the same priority (last one always wins).
4 Functions Application overview 4.4 Application overview The thermostats support the following applications, that can be configured using the DIP switches inside the front panel of the unit or a Modbus commissioning tool. Remote configuration All DIP switches need to be set to OFF (factory setting) to select an application via commissioning tool.
Functions Application overview 4 4.4.
4 Functions Application overview 4.4.
Functions Application overview 4 4.4.
4 Functions Additional functions 4.
4 Functions Additional functions 4.5.1 Sensors and changeover functions Heating/cooling changeover via Modbus (P01) Heating/cooling changeover information is received via Modbus. This is possible only when the control sequence is set to automatic heating/cooling changeover (P01 = 3) and no local input (B1/X1/S1) is assigned to this function. Required information is unavailable (e.g., due to data communication problems, power failure, etc.
4 Functions Additional functions Manual heating/cooling changeover (P01) ● ● ● External/return air temperature sensor (P38/P40) An external switch is connected to B1/X1/X2 (P38/P40 = 9) to change heating/cooling mode remotely. Manual heating/cooling changeover means selection via changeover button on the thermostat by repeatedly pushing the button until the required mode is displayed (automatic changeover via external sensor / switch connected to B1/X1/X2).
4 Functions Additional functions 4.5.4 Monitoring and limitation functions Floor temperature limitation function (P51) The floor temperature should be limited for two reasons: Comfort and protection of the floor. The floor temperature sensor, connected to multifunctional input B1/X1 or S1/X2, acquires the floor temperature. If the temperature exceeds the parameterized limit (P51), the heating valve is fully closed until the floor temperature drops below the parameterized limit.
4 Functions Additional functions 4.5.5 User operation / Indication Key lock (P14) If the "Key lock" function is enabled by P14, lock or unlock all buttons by pressing the operating mode button for 5 seconds. If "Auto lock" is configured, the thermostat automatically locks the buttons 10 seconds after the last adjustment; unlock the buttons as per manual locking.
Functions Control sequences 4 4.6 Control sequences 4.6.1 Overview of Sequences (setting via P01) The main control sequence (water coil sequence of the fan coil unit) can be set via P01. The following sequences can be activated in the thermostats (with or without auxiliary heating). The available sequences depend on the application (selected via DIP switches, see Application overview [➙ 22]).
4 Functions Control sequences 4.6.2 2-pipe fan coil unit In 2-pipe applications, the thermostat controls a valve in heating/cooling mode with changeover (automatically or manually), heating only, or cooling only (factory setting, P01 = 1). On/Off control Control sequence On/Off output The diagrams below show the control sequence for On/Off control.
4 Functions Control sequences 4.6.3 2-pipe fan coil unit with electric heater (RDF660MB only) Heating or cooling with auxiliary heater In 2-pipe applications with electric heater, the thermostat controls a valve in heating/cooling mode with changeover, heating only, or cooling only plus an auxiliary electric heater. Cooling only is factory-set (P01 = 1) with enabled electric heater (P13).
4 Functions Control sequences Heating mode (automatic changeover = heating or heating only) Cooling mode (man. / auto.
4 Functions Control sequences 4.6.4 4-pipe fan coil unit Heating and cooling In 4-pipe applications, the thermostat controls 2 valves in heating and cooling mode, heating/cooling by manual selection, or heating and cooling with changeover. Heating and cooling (P01 = 4) is factory-set. 4-pipe application with manual changeover The heating or cooling output can be released via operating mode button if P01 is set to Manual (P01 = 2).
4 Functions Control sequences 4.6.5 Chilled/heated ceiling and radiator applications For chilled/heated ceiling and radiator applications ● Set the corresponding basic application see Application overview [➙ 22].
Functions Control sequences 4 4.6.7 Setpoints and sequences 2-pipe applications In changeover applications, the Comfort setpoints for the heating and cooling sequences are identical (w). In 2-pipe applications with electric heater (RDF660MB only), the Comfort setpoint is either at the first heating sequence (in heating mode) or at the cooling sequence (in cooling mode). The setpoints for Economy and Protection are below the Comfort setpoints (for heating) and above the Comfort setpoints (for cooling).
4 Functions Control outputs 4.7 Control outputs 4.7.1 Overview Overview of control outputs Different control output signals are available and defined during commissioning (see below). Control output On/Off 3-position Y1, Y2 (2 x SPST) Y1, Y2 * (1 x / Product No. RDF660MB/MM RDF660MB *) ) Only on 2-pipe application On/Off control signal (2-position) The valve receives the Open/On command via control output Y1 or Y2, if 1.
Functions Fan control 4 4.7.2 Control output configuration (setting via DIP switches or Modbus commissioning tool) For the control outputs of a 2-pipe application, either On/Off or 3-position can be set via DIP switches or Modbus commissioning tool (see Application overview [➙ 22]). Other applications, e.g. 4-pipe and 2-pipe with electric heater (RDF660MB only), only have On/Off type of outputs. The application and control output can be changed between On/Off and 3-position via Modbus. Plant type 4.
4 Functions Fan control Fan control with On/Off heating/cooling control In applications with On/Off (2-position) control: 1. The switching point for low fan speed is synchronized to the heating / cooling output. 2. The maximum switching range of the fan (XpHFan /XpCFan) is defined by the switching differential (SDH/SDC) via a look-up table. Heating/cooling DC 0...10 V fan T [°C] w Q Y SDH SDC Look-up table with On/Off (2-position) control Manual operation DC 0...
4 Functions Fan control This function allows users to use the thermostat in universal applications such as chilled/heated ceilings and radiator, etc. (see Chilled/heated ceiling and radiator applications [➙ 36]). Fan minimum on- time In automatic mode, a dwelling time of 2 minutes (factory setting) is active. The fan maintains each speed for at least 2 minutes before it changes to the next speed. The minimum on-time can be adjusted from 1…6 minutes via parameter P59.
4 Functions Fan control Clean fan filter reminder The "Clean fan filter reminder" function counts the fan operating hours and displays message "FIL " to remind users to change/clean the fan filter as soon as the threshold is reached. This does not impact the thermostat's operation, which continues to run normally. The function is set via parameter P62 (Service filter). The "Clean filter reminder" is reset when the operating mode is manually set to Protection and back.
Functions Multifunctional input, digital input 4 4.9 Multifunctional input, digital input The thermostat has 2 basic inputs B1/X1 and S1/X2. An NTC type sensor such as NTC 3k (AI, analog input) or a switch (DI, digital input) can be connected to the input terminals. The functionality of the inputs can be configured via P38 and P39 for B1/X1, P40 and P41 for S1/X2. The current temperature or state of the inputs B1/S1/X1/X2 is available on Modbus for monitoring purposes.
4 Functions Multifunctional input, digital input # Function of input Description Type B1/S1/X1/ X2 7 Monitor input (digital) (RDF660MB only) Digital input to monitor the state of an external switch via Modbus DI 8 Monitor input (analog) (RDF660MB only) Sensor input to monitor the state of an external sensor (e.g., NTC 3k) via Modbus. AI 9 Heating/cooling changeover Digital input for "Automatic heating/cooling changeover" function. A switch instead of a sensor can also be connected.
4 Functions Handling system faults 4.10 Handling system faults Temperature out of range If the room temperature exceeds or drops below the measuring range, i.e. above 49 °C or below 0 °C, the limiting temperatures blink, e.g., 0 °C or 49 °C. In addition, the heating output is activated if the current setpoint is not set to Off, the thermostat is in heating mode and the temperature is below 0 °C. For all other cases, no output is activated.
4 Functions Modbus RTU mode The table below shows error codes and default alarm texts.
Functions Communication objects 4 4.12 Communication objects 4.12.1 Overview Object No. and name Thermostat Object No.
4 Functions Communication objects 4.12.
4 Functions Communication objects Address (Decimal) Register length (bytes) Read only (RO) or Read/Write (R/W) Function code (HEX) 0x03--Read holding registers 0x04--Read input registers 0x06--Write single register 0x10--Write multiple registers Special process Default value 20 Modbus data frame format P83 0003 1 R/W 0x03 0x06 - 0 21 Control sequence if 2-pipe applications are selected P01 0004 1 R/W 0x03 0x06 - 1 22 Control sequence if 4-pipe application is selected Mode select
Functions Communication objects Read only (RO) or Read/Write (R/W) Function code (HEX) 0x03--Read holding registers 0x04--Read input registers 0x06--Write single register 0x10--Write multiple registers Special process Default value 44 Register length (bytes) 43 Integral action time Tn H/C changeover switching point cooling H/C changeover switching point heating Input X1 (RDF660MB only) Address (Decimal) 41 42 Object Write Related parameter Object no.
4 Functions Communication objects Address (Decimal) Register length (bytes) Read only (RO) or Read/Write (R/W) Function code (HEX) 0x03--Read holding registers 0x04--Read input registers 0x06--Write single register 0x10--Write multiple registers Special process Default value 54 Fan control P52 0037 1 R/W 0x03 0x06 - 1 55 P54 0038 1 R/W 0x03 0x06 - 60 s 56 57 58 59 Fan overrun time (RDF660MB only) ECM fan max. output ECM fan min. output Fan min.
4 Functions Communication objects Address (Decimal) Register length (bytes) Read only (RO) or Read/Write (R/W) Function code (HEX) 0x03--Read holding registers 0x04--Read input registers 0x06--Write single register 0x10--Write multiple registers Special process Default value 76 System time - 0201 ...
4 Functions Control parameters 4.13 Control parameters To optimize control performance, a number of control parameters can be readjusted on the thermostat via HMI, commissioning/operating tool. These parameters can also be set during operation without opening the unit. In the event of a power failure, all control parameter settings are retained.
4 Functions Control parameters 4.13.
Functions Control parameters 4 4.13.4 Expert level parameters with diagnostics and test Parameter Name Factory setting Range Expert level P30 Heat P-band Xp/switching differential 2K 0.5…6 K P31 Cool P-band Xp/switching differential 1K 0.5…6 K P32 Integral time (fan) 0 min 0 …20 min P33 Dead zone Comfort mode 2K 0.5…5 K P34 Setpoint differential 2K 0.5…5 K P35 Integral action time Tn 45 min 0...
4 Functions Control parameters Parameter Name Factory setting Range Power of electric heater on Y2 (for adaptive temperature compensation) (RDF660MB only) 0 0.0...1.2 kW P48 2-pos output minimum ON time 1 min 1...20 min P49 2-pos output minimum OFF time 1 min 1...20 min P50 Purge time 0 0 = Inactive or 1…5 minutes P51 Floor heating temperature limitation (RDF660MB only) 0 0 = Off or 10...50 °C P52 Fan control 1 0 = Disabled Expert level P45 resolution 0.
4 Functions Control parameters Diagnostics and test Parameter Name Factory setting Range - NONE = (No application) Service level d01 Application number 2P = 2-pipe 2P3P = 2-pipe 3-position 2PEH = 2-pipe with electric heater 4P = 4-pipe d02 X1 status - "---" = Function not selected 0 = Not activated (for DI) 1 = Activated (DI) 0…49 = Current temp.
5 Connection Connection terminals 5 Connection 5.1 Connection terminals RDF660MB/MM RDF660MB L, N Operating voltage AC 230 V Y50 DC 0...10 V fan output M Reference for DC fan Y1, Y2 Control output “Valve” AC 230 V (N.O., for normally closed valves), output for compressor or output for electric heater B1, S1 Multifunctional input for temperature sensor (e.g. QAH11.
5 Connection Connection diagrams 5.2 Connection diagrams Application 2-pipe, 2-position 2-pipe, 3-position 4-pipe 1-stage compressor (heating and/or cooling) 1-stage compressor with electric heater (RDF660MB only) N1 Room thermostat RDF660MB/MM, RDF660MB C1, C2 1-stage compressor V1 Valve actuator, 2- or 3-position V1, V2 Valve actuator, 2-position S2 Switch (keycard, window contact, presence detector, etc.
6 Technical data 6 Technical data Power supply Operating voltage AC 230 V +10/-15 % Frequency 50/60 Hz Power consumption 9 VA ● No internal fuse! External preliminary protection with max. C 10 A circuit breaker required in all cases. Outputs DC fan control DC 0…10 V; Y50 SELV DC 0…10 V, max. 5 mA Control output Y1-N / Y2-N (N.O.) Rating AC 230 V Max.
6 Technical data Operational data Switching differential, adjustable Heating (P30) 2 K (0.5…6 K) Cooling (P31) 1 K (0.
6 Technical data Standards and directives Pollution class Class 2 Degree of protection of housing IP30 as per EN 60529 Housing flammability class according to UL94 V-0 Environmental compatibility The product environmental declaration (A5W00139322A *) contains data on environmentally compatible product design and assessments (RoHS compliance, materials composition, packaging, environmental benefit, disposal). General Connection terminals Solid wires or prepared stranded wires 1 x 0.4…1.
Dimensions 7 7 Dimensions Dimensions in mm Dimensions in mm A6V12114068_en--_c 63 | 66
Index Index 3 3-position control signal.................................... 38 A Automatic heating / cooling changeover via bus ............................................................................ 27 Automatic heating/cooling changeover ....... 27, 31 B Basic application ............................................... 36 C Changeover switch ............................................ 27 Changeover via Modbus ............................... 43, 44 Chilled/heated ceiling applications ..........
Index W Window contact ......................................
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