Ramsey Pro-Line Under Speed Switches

There are two types of switches that sense under speed conditions in rotating equipment.

The Ramsey Pro-Line Model 60-23P Under Speed Switch monitors speed by sensing a ferrous element attached to the rotating shaft or equipment. The detector generates impulses from the ferrous element and closes alarm contact when the time between impulses is greater than the time adjusted by the setpoint. The unit operates on the number of impulses received rather than actual revolutions. Low speed range may be enhanced by increasing the number of ferrous elements on the rotating shaft.

The Ramsey Pro-Line Model 60-23A Under Speed Switch monitors the speed of a rotating shaft. It is directly coupled to the rotating shaft and will detect one-to-one rotation of the shaft.