Temperature monitoring

Motor winding temperature, discharge gas temperature or oil temperature are monitored by PTC resistors. The compressor protection device locks out immediately when the resistor in the temperature control circuit exceeds a specified value.

3 or 6 PTC resistors according to DIN 44081/82 are generally installed in the motor winding. Up to 9 series-connected PTC can be used.
Cable lengths > 30 m are not tested during type approval!
The control circuit operates at low voltage and must not come into contact with supply voltage.

For compressors that are delivered with the compressor protection device already installed in the terminal box, this protection function is in most cases fully wired and connected to the compressor protection device.

Further information on wiring can be found in the schematic wiring diagrams, in the connection diagrams or on the adhesive label in the compressor's terminal box.

CSH and CSW screw compressors − Example: connection diagram for SE-E1 / SE-E3 protection devices with a sensor for discharge gas and/or oil temperature (R2) and an oil heater (R1)

ECOLINE reciprocating compressor: wiring information on the adhesive label in the terminal box