SPL Series

  • Combination indicating gage and critical temperature limit switches
  • High and low temperature limit contacts are visible and adjustable
  • Panel and wall mount versions
  • Latching control relay versions available

FW Murphy Production Controls offers support for all our products. If you are unable to find the product that you need, please call us at 918-957-1000.

Stage V: 
Product Overview: 

The 4-1/2” (114 mm) size dial gage is a mechanical gage for temperature indication. It is a combination indicating gage and critical temperature limit switches. High and low temperature limit contacts are visible.

It includes adjustable, electrical contacts that can be used for start and stop, to trip alarms and to shut down equipment.

Panel and wall-mount versions are available as well as latching control relay versions.

Ranges are available from 15° to 250° F (9° to 121° C) through 260° to 450° F (127° to 232° C).

Typical applications include:

  • Gas compressors
  • Heaters and coolers
  • Water pump temperature
  • Engine coolant temperature
  • Process temperature

Basic Models

SPLC Series gage: Surface-mount version of the gage. For these models the gage pointer makes with two adjustable contacts to complete a pilot-duty circuit.

SPLFC Series gage: Panel-mounting (round case) version of the SPLC.

We offer square case configurations altered to fit round panel openings, see Dimensions.

Basic Operation

This vapor-actuated gage features a sealed capillary tube and sensing bulb. When subjected to heat, the liquid in the sensing bulb expands to vapor creating pressure against a bourdon tube mechanism. The bourdon tube translates this vapor pressure into a mechanical gage reading.

For models SPLC and SPLFC, the gage pointer acts as a pressure indicator and as one switch pole, which completes a circuit when it touches the adjustable limit contacts. Contacts have self-cleaning motion to ensure electrical continuity. A toggle switch is provided on SPLC models to override the low contact for equipment start-up.

Mechanical Gauges (Temperature)