Danfoss Oil Pressure Switch

MP 54 and MP 55 oil differential pressure switches are used as safety switches to protect refrigeration compressors against low lubricating oil pressure.

If the oil pressure fails, the oil differential pressure switch stops the compressor after a certain time period.

MP 54 and MP 55 are used in refrigerating systems using HCFC and non-flammable HFC refrigerants.

MP 55A is used in refrigerating systems with R717. MP 55A can also be used in systems with HCFC and non flammable HFC refrigerants.

MP 54 has a fixed differential pressure setting. It also incorporates a thermal time relay with a fixed release time setting.

MP 55 and MP 55A have adjustable differential pressure and are available both with and without thermal time relay.


  • Wide regulating range
  • Can be used for deep freeze, refrigeration and air conditioning plant
  • Can be used for HCFC and non-flammable HFC refrigerants
  • Electrical connection at the front of the unit
  • Suitable for both alternating and direct current (AC and DC)
  • Screwed cable entry for cables from 6 –14 mm diameter
  •  Small contact differential