The microprocessor-controlled controller ST501-KU3KAR.112 consists of a service and a separate power pack plate and is used for thermostatic temperature regulation in simple refrigerating plants. It is supplied with 230V AC and has four relay outputs as well as an exit for a DC voltage fan.
The relays can be used for different functions, e.g. for a compressor, a defroster, an alarm relay, etc. (see parameters U1-U4). The two resistance sensors seize the refrigerating chamber temperature and the evaporator temperature. Networking of the controller takes place via the ST-Bus interface.