Technical Info

Engineering Notes | Design Equations | Flexivity Values | Glossary

Trip Temperature
The temperature at which snapover occurs when the element is heated.

Reset Temperature
The temperature at which the bimetal element reverses itself when cooled.

Delta
The difference in temperature between trip temperature and reset temperature. Generally delta is not less than 15°F.

Tolerance
The accuracy of the temperature response of the snap element. Usually it is ±2°F or more.

Movement
The total distance traveled by the work point of the element when snap-over occurs at the trip temperature.

Creep
The amount of movement by the work point of the element when heated from ambient temperature to the trip temperature, but not including snap-over.

Trip Side
For discs that have their trip above room temperature, the high expansion
side of bi metal, is the concave side of the element before reaching the
trip temperature. The rule is opposite when the trip temperature is below
room temperature.

Reset Side
For discs that have their reset above room temperature, the low expansion
side of bimetal, is the convex side of the element before reaching the reset
temperature. The rule is opposite when the reset temperature is below room temperature.

Load
Any physical force applied to either side of the snap element.
e.g. spring, fluid pressure, vibration, magnetism.