N1 Room thermostat RDF302...
M1 1- or 3-speed fan
V1 Valve actuator, 2- or 3-position
V1, V2 Valve actuator, 2-position
E1 Electric heater
C1, C2 1-stage compressor
S1, S2 Switch (keycard, window contact,
presence detector, etc.)
B1, B2 Temperature sensor (return air
temperature, external room
temperature, changeover sensor, etc.)
+ RS485 Modbus connection
- RS485 Modbus connection
REF RS485 signal/common ground
(Differential common)
RDF302.B does not have inputs X1, X2 and M.