Combination Indicating Gage and Limit Switch
Critical/High Temperature Limit Switch Is Visible and Adjustable (Most Models)
Switch Can Activate Alarms and/or Shut Down Equipment
Contact Grounds Through Case
The 20 Series (2 inch/51 mm dial) and the 25 Series (2-1/2 inch/64 mm dial) Swichgage models are diaphragm-actuated, temperature-indicating gages with built-in electrical switches for tripping alarms and/or shut-down devices.
Ranges are available from 32°-120°F (0°-45°C) through 300°-440°F (160°-220°C).
The gage mechanism is enclosed in a steel case coated to resist corrosion. A polycarbonate, break- resistant lens and a polished, stainless steel bezel help protect this rugged, built-to-last instrument.
These vapor-actuated gages feature a sealed capillary tube and a sensing bulb. When subjected to heat, the liquid in the sensing bulb changes to vapor creating pressure against the diaphragm mechanism. The diaphragm translates this vapor pressure into a mechanical gage reading.
For series 20T and 25T, the gage pointer acts as a temperature indicator and as one switch pole which completes a circuit when it touches the adjustable limit contact. Contact(s) are grounded through the Swichgage case. They have a self-cleaning motion to enhance electrical continuity.
These instruments are used on equipment in oil field and monitoring engine coolant, crankcase oil and transmission oil.