Modbus variable list
C.5 Input Register
Modbus address Description Scale
1 Regin Model number (=1751) 1
2-3 Not used
4 Status
0 = Beta status
1 = Released version
1
5-7 Not used
8 Heating/cooling mode
0 = Not used
1 = Heating
2 = Cooling
1
9 Controller state
0 = Off
1 = Not used
2 = Standby
3 = Not used
4 = Occupied
1
10 Room temperature
The current room temp, from internal or external sensor
10
11 Change-over temperature
The current change-over temp. Shows NaN! if no sensor is connected.
10
12-19 Not used
20 Room temperature (internal)
The value from the internal NTC sensor
10
21 Room temperature (external)
The value from the external temperature sensor. Shows a value if a temperature
sensor is configured for AI1, NaN! otherwise
10
22 Change-over temperature
The value from the external change-over temperature sensor. Shows a value if a
change-over sensor is configured for AI1, NaN! otherwise
10
23-24 Not used
25 AI Temp Raw
Raw value of the terminal (before any filters). Shows NaN! if no sensor is connected
10
26 Not used
27 AI Temp
Value of the Analog input after filters and scaling. Shows NaN! if no sensor is
connected
10
28 Not used
29 Calculated setpoint
The setpoint for the controller (SP
calc
), calculated from the basic setpoint, setpoint
adjustment and hysteresis.
10
30-32 Not used
C.6 Holding Register
Modbus
adress
Description Unit Default
value
Scale Min
value
Max
value
1 Basic setpoint (SP
basic
) °C 220 10 50 500
2 Hysteresis to calculate Heating and Cooling setpoint at Occu-
pied state
°C 20 10 10 400
RCFD-230C manual, Rev. A 27