Thermal Switch Monitors Oil Temperature

A large US based military vehicle company contacted us about a version of our thermostat that they could use in a harsh environment, high temperature application. They needed the device to be very rugged and robust but based on common commercial products with a long experience of performance in the field and quick availability.

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Thermal Switch Monitors Oil Temperature

The application was to improve the cold start ability of their approx. 500hp diesel engine. The thermal switch is crucial as it monitors the engine oil temperature, triggering a cold start process when the temperature is near or below freezing. The key requirement was to have the snap disc thermostat mount in a 1/2 NPT thread hole that they already had on their equipment.

Thermal Switch Monitors Oil Temperature

We didn’t have any bimetal thermostats that met their description on our shelf, but were able to quickly adapt a unit for this application. The unit was machined and tested in a few weeks to get them test samples. This included using their specified high temperature cables. (200ºC 16AWG)

These devices were calibrated to insure the temperature performance in the new housing was consistent. The large contact surface with the engine allowed the limit style snap switch to match the temperatures very closely. These ‘limit’ style switches turned the system on at or below 32 degrees and turned the cold start system off once the temperature increased to 42 degrees F.

Our temperature switches work by using a bimetal disc. The bimetal disc in the switch reacts to heat, and opens or closes a set of contacts based on what the ambient temperature is. This is works because the different metals in the disc react to heat in different ways, which causes the disc to bend.

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The superior controls manufactured by Senasys have a history of solid performance in many industries. From 22.5 mm selectors, to the four quadrant lighted feedback CMC controls, almost any switching need can be, and has been utilized in a variety of applications. Select a group below for more information. When you have found a switch that fits your needs, simply fax or email your specs to us and let our highly trained engineers find the most efficient configuration for your applications.

Custom Soltutions

Senasys products are designed & manufactured to meet the needs of original equipment manufacturers worldwide.

Made in U.S.A.

Senasys products are designed & manufactured in Eau Claire, Wisconsin, U.S.A.