Reversing Relay (M25)

The Model 25 Reversing Relay is designed for applications requiring an output that equals a manually preset spring load minus a variable signal pressure. This high quality unit combines excellent sensitivity with unusually high flow capacity. The Model 25 is ideally suited for a variety of precision control applications, including converting direct acting valves to reverse action, controlling opposite acting valves from a single transmitter, and cushioning cylinder loads. The basic mathematical expression for the Model 25 is PO = K - PS where PO is output pressure, PS is signal pressure and K is the spring constant.


  • Control Sensitivity of 1/8" water column
  • Balanced supply valve
  • Aspirator tube design
  • Separate control chamber isolates
  • Unit construction


  • Allows for use in high precision applications
  • Minimizes the effects of supply pressure variation
  • Compensates for output pressure droop under flow conditions
  • Isolates the diaphragm from the main flow to eliminate hunting and buzzing
  • Allows servicing without removal from air line

See PUB103-069 for further information.

Reversing Relay (M25)