FW Murphy, 20700222, SHD30 Digital Tach/Hourmeter with Adjustable Overspeed Trip Point, Backplate with Studs to Mount
It is microprocessor-based tachometers with hourmeter and an overspeed trip point. The trip point can be connected as either a form C relay output or as a normally open SCR output for alarm or shutdown on overspeed.
It features a panel-mounting design, plastic enclosure that is 5-1/16 (129 mm) long and 4-1/4 in. (108 mm) high. It has a backplate with studs to mount.
The power and RPM data are supplied by either a magnetic pickup or a capacitor discharge (CD) ignition. The hourmeter is adjustable to a preset time and resettable to zero. Should power be lost, onboard batteries maintain the run hours display and allow for resetting the overspeed relay output.
When a tach signal is present it display RPM. When a tach signal is not present, the display is blank unless the Read Hours membrane key on the faceplate is pressed and held.
The five-digit, liquid crystal display is updated every second. The run hours, overspeed set point and current pulses per engine revolution can be displayed by manipulating the membrane switches. Run hours can be displayed even after power is lost. The run hours display can be configured to alternate with the RPM display.
Applications:
- Gas Compressors
- Oil Field Equipment
For more information, please see 
Data Sheet
