Application

OUT571 differential oil pressure sensor servers to monitor the oil differential pressure of oil pumps in refrigeration compressors. For this a screw-in part that is mounted directly in the pump housing is evaluated for differential pressure measurement. The screw-in part is thereby connected by internal channels with the suction and high pressure side of the pump. Supplementary pipe connections are not needed. The evaluation unit is fastened by a coupling ring in the screw-in part and can be removed without opening the oil/refrigeration circuit. Once the supply voltage has been switched on, the relay trips after a 3 second delay time. With the operating recognition signal, which is applied to D1 of motor contactor (may see wiring diagram), the differential pressure monitoring is activated after the expiration of a starting transition time. A missing differential pressure leads to a locked switch off after 90 seconds; with differential pressure fluctuation appropriately later (time integration). The monitoring of internal errors is always active.

Any faults that occur in any operational phase lead to a locked switch off of the relay after 5 seconds.

The potential-free contact can be looped into a safety circuit without an auxiliary relay. An installation check monitors the proper assembly. The built-in LED indicates the operating state.

Wiring diagram