Differential Pressure Switch for Refrigeration application Model DPSM-690 (WIKA)
Applications
- Compressors
- Driers
- HVAC
- Cold storage
- Chillers
Special features
- Wide adjustable range
- In-built sturdy mechanism
- Manual reset
- Time delay relay
Description
Type DPSM-690 is used as a safety device on pressure lubricated refrigeration compressors, where under any operating conditions the lubricating oil pressure has to be kept higher than the suction pressure or crankcase pressure. The bellows marked OIL is connected to outlet side of compressor or at discharge from crankshaft lubrication system, and measures the lubricating oil pressure P1. Bellows marked LP is connected to the compressor crankcase and measures the crankcase pressure P2.
Differential Pressure (P1–P2) is the pressure available for the lubrication system. If during start up, differential pressure fails to reach the set value, or if during operation differential pressure falls below the set value, the control device breaks the circuit to compressor motor after an allowable time delay.
Once the circuit is broken, it has to be reset manually by pressing the reset knob.
Related products
Differential Pressure Switch mechanical Model DPSM-550 (WIKA)