Product Specifications

Low Voltage Snap-Action Temperature Controls

The 44T series of controls is specifically designed for low voltage and millivolt circuit applications. Gold-plated contacts and tin-plated terminals, high contact pressure, ultrasonic cleaning and epoxy sealing assure a clean switching environment and repeatable low resistance operation. A variety of terminals, lead wire and mounting configurations, as well as a wide range of temperature calibrations, are available to provide maximum application flexibility.

Features and Benefits:

• Low internal resistance (maximum .003 ohms across terminals).

• Clean switching environment.

• Epoxy sealed for resistance to contamination from the application environment.

• Wide range of available calibration temperatures.

• Large selection of terminals and lead wires.

• Surface, airstream or stud mounting configurations.

• 3/4” snap-action disc for high-speed contact separation and long life.

Switch Actions and Typical Applications:

The 44T is an automatic reset single pole, single throw (SPST) switch that is designed to open its electrical contacts on temperature rise. Once the temperature in the application has returned to the specified reset calibration, the switch will automatically return to the closed position.

Typical uses of the Therm-O-Disc 44T include limiting or regulating temperatures in gas appliances and heating systems that require the thermostat to make/break the millivolt circuit of a thermocouple or the low voltage circuit of other types of devices. For low voltage applications requiring a “one-shot” or fuse operation, the 44F is a SPST switch whose contacts open on temperature rise. However, the 44F is a single operation device. Once the switch has operated, the “fuse” disc prevents reset of the contacts to their closed state at temperatures above -31°F (-35°C).