BITZER · Refrigeration controller
CM-RC-01 compressor control module (IQ module) Modbus register map
Default configuration
- Protocol
- RS485
- Port
- 502
- Unit ID
- 48
- Addressing
- 1-based
- Byte order
- Big endian
- Word order
- High word first
- Baud rate
- 19200
- Parity
- Even
- Data bits
- 8
- Stop bits
- 1
This device has an RS-485 interface. Reach it through a Modbus RTU-to-TCP gateway, configured with the factory serial settings above.
Register map
| Address | Count | Name | Type | Unit | Scale | Access |
|---|---|---|---|---|---|---|
| 100 | 1 | Capacity setpoint Active capacity setpoint. Transmitted with scale 100 (12.3 % = 123). | Int16 | % | 0.01 | R |
| 101 | 1 | Actual capacity Average capacity delivered. Transmitted with scale 100. | Int16 | % | 0.01 | R |
| 102 | 1 | Control word Active control word. | UInt16 | - | 1 | R |
| 103 | 1 | Status word Operation status word. | UInt16 | - | 1 | R |
| 11100 | 1 | Number of active alarms Number of active alarms. | UInt16 | - | 1 | R |
| 11101 | 1 | Number of uncleared listed alarms Number of listed alarms that have not yet been cleared. | UInt16 | - | 1 | R |
| 11102 | 1 | Highest alarm state 0 = Clear, 1 = Inactive, 2 = Active, 3 = Set. | UInt16 | - | 1 | R |
| 11103 | 1 | Highest alarm severity 0 = None, 1 = Log, 2 = Event, 4 = Info, 8 = Warning, 16 = Critical, 32 = Fault. | UInt16 | - | 1 | R |
| 11104 | 1 | Waiting for external reset 0 = No, 1 = Yes. Set when the module is locked and waiting for an external reset command or restart. | UInt16 | - | 1 | R |
| 11105 | 1 | Required alarm reset level 0 = NA, 1 = Auto, 2 = Timer, 3 = Extern, 4 = Restart. | UInt16 | - | 1 | R |
| 11201 | 1 | Highest ranked alarm code Code of the highest ranked active alarm. | UInt16 | - | 1 | R |
| 11202 | 1 | Second highest ranked alarm code Code of the second highest ranked active alarm. | UInt16 | - | 1 | R |
| 12001 | 1 | Suction pressure Suction pressure. Transmitted with scale 100. | Int16 | bar(a) | 0.01 | R |
| 12002 | 1 | Discharge pressure Discharge pressure. Transmitted with scale 100. | Int16 | bar(a) | 0.01 | R |
| 12003 | 1 | Evaporating temperature (SST) Calculated saturated suction temperature. Transmitted with scale 10. | Int16 | °C | 0.1 | R |
| 12004 | 1 | Condensing temperature (SDT) Calculated saturated discharge temperature. Transmitted with scale 10. | Int16 | °C | 0.1 | R |
| 12005 | 1 | Envelope status 0 = Stopped, 1 = Starting, 2 = Running, 3 = Stopping, 4 = Warning - inside envelope, 5 = Critical - outside envelope, 6 = Fault. | UInt16 | - | 1 | R |
| 12006 | 1 | Envelope zone 0 = Inside, 1 = SST Low / SDT Low, 2 = SST Low, 3 = SST Low / SDT High, 4 = SDT High, 5 = SST High / SDT High, 6 = SST High, 7 = SST High / SDT Low, 8 = SDT Low. | UInt16 | - | 1 | R |
| 12010 | 1 | Discharge temperature Discharge gas temperature. Transmitted with scale 10. | Int16 | °C | 0.1 | R |
| 12011 | 1 | AUX temperature Auxiliary temperature input. Transmitted with scale 10. | Int16 | °C | 0.1 | R |
| 12022 | 1 | High pressure switch 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 12023 | 1 | Crankcase oil heater 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 12025 | 1 | Oil sensor 1 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 12026 | 1 | Oil sensor 2 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 12027 | 1 | Motor start requested 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 12028 | 1 | Head cooling fan 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 12029 | 1 | Liquid injection cooling valve 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 12030 | 1 | Compressor start unloading valve 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 12031 | 1 | Capacity control valve CR-1 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 12032 | 1 | Capacity control valve CR-2 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 12033 | 1 | Capacity control valve CR-3 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 13001 | 1 | Motor overheat thermistor resistance PTC thermistor resistance of the motor overheat protection. | UInt16 | Ohm | 1 | R |
| 13002 | 1 | Estimated motor power consumption Estimated motor power. Transmitted with scale 10. | UInt16 | kW | 0.1 | R |
| 13003 | 1 | Motor drive frequency Motor drive frequency (speed). Transmitted with scale 10. | UInt16 | Hz | 0.1 | R |
| 13006 | 1 | Motor start contactor 1 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 13007 | 1 | Motor start contactor 2 0 = Off, 1 = On. | UInt16 | - | 1 | R |
| 14000 | 1 | System operating state 0 = CONFIG, 1 = INPUT, 2 = STARTUP, 3 = READY, 4 = SUSPEND, 5 = SERVICE, 6 = PRODUCTION. | UInt16 | - | 1 | R |
| 15150 | 1 | Control output current Control output current. Transmitted with scale 100. | Int16 | A | 0.01 | R |
| 15990 | 1 | Operation LED state 0 = OFF, 1 = ON, 2 = SLOW_SHORT, 3 = SLOW_MED, 4 = SLOW_LONG, 5 = FAST_SHORT, 6 = FAST_MED, 7 = FAST_LONG. | UInt16 | - | 1 | R |
| 15991 | 1 | Warning LED state 0 = OFF, 1 = ON, 2 = SLOW_SHORT, 3 = SLOW_MED, 4 = SLOW_LONG, 5 = FAST_SHORT, 6 = FAST_MED, 7 = FAST_LONG. | UInt16 | - | 1 | R |
| 15992 | 1 | Fault LED state 0 = OFF, 1 = ON, 2 = SLOW_SHORT, 3 = SLOW_MED, 4 = SLOW_LONG, 5 = FAST_SHORT, 6 = FAST_MED, 7 = FAST_LONG. | UInt16 | - | 1 | R |
| 15993 | 1 | Communication LED state 0 = OFF, 1 = ON, 2 = SLOW_SHORT, 3 = SLOW_MED, 4 = SLOW_LONG, 5 = FAST_SHORT, 6 = FAST_MED, 7 = FAST_LONG. | UInt16 | - | 1 | R |
| 20300 | 1 | Serial control source 0 = None, 1 = COM1 (Modbus). | UInt16 | - | 1 | R |
| 20301 | 1 | Serial control timeout function 0 = None, 1 = Stop, 2 = Fault. | UInt16 | - | 1 | R |
| 20302 | 1 | Serial control timeout time Serial control timeout time, default 60 s. | UInt16 | s | 1 | R |
| 22100 | 1 | Refrigerant selection 0 = NONE, 1 = R134a, 2 = R404A, 3 = R507A, 4 = R407C, 5 = R22, 6 = R407A, 7 = R407F, 9 = R448A, 10 = R449A, 11 = R450A, 12 = R513A, 13 = R1234yf, 14 = R1234ze. | UInt16 | - | 1 | R |
| 22300 | 1 | Mains supply voltage specification Mains supply voltage specification (single phase). | UInt16 | V | 1 | R |
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Related guides
Notes
Source: BITZER "Reference guide - Compressor Control Module CM-RC-01", document version 3.0, sections 10.2 and 10.3 (http://cis.bitzer.ru/files/File/IQ-Products/CM-RC-01.pdf, BITZER's own Russian documentation server). The guide states that the numbers in section 10.3 are Modbus register numbers, not indexes, so they are one-based register numbers and the PDU address is one less; every input register can also be read as a holding register. Factory serial settings from section 10.2.1: address 48, 19200 bps, 8 data bits, even parity, 1 stop bit. Scale 100 / scale 10 values are transmitted as 100x / 10x the engineering value, hence scale factors 0.01 / 0.1. The module is reached over RS-485 through a Modbus RTU-to-TCP gateway. Only 16-bit points are listed: the file leaves out the 32-bit counter pairs (device and compressor operating hours, start count) because their word order is not stated unambiguously in the extracted table. COM1 configuration registers are listed read/write because the module allows changing them over Modbus, although the factory values above are the ones to start from.