Measurements are never precise and the temperature tolerance is no exception. You will need to determine what range of temperatures are acceptable for your particular application. Even a ruler isn’t exactly 12 inches. If you take a measurement out to enough decimal places, you’ll find some level of variation from what it claims to be. This is the same with temperature. After you have determined the correct tolerance for your application, view our selection of automatic reset switches to purchase.
The temperature tolerance of a switch tells us the acceptable level of variation it may have and is commonly called out with a “±” symbol . For example, a switch that opens at 100°F with a 5°F tolerance could open anywhere between 95°F and 105°F. This would be written out as 100°F ± 5°F.
Senasys has two general specifications on the thermostat temperatures tolerances.
Snap disc thermostats commonly have between a ± 5°F and ± 10°F tolerance on both the open and closing temperatures. Tighter tolerances are possible but are more difficult to achieve. To consistently achieve a tighter tolerance, you would need to have a switch with a digital component. Snap discs are entirely mechanical, so they can only be so precise. So, if we say the device opens at 95ºF it will open between 90 and 100ºF (with the most common +/- 5º setting).
Our other style is called a min/max and for those units we just specify the outer temperatures with a 10 or 15 degree hysteresis. For example as 125-115 min/max open on rise switch will open by 125 and close by 115. Generally these would open around 122 to 125 and reset by 118 to 115. However, they may change at 122 and 120 giving a small hysteresis as well.
Custom tolerances are easily available to help manage your thermal systems. Also, for all of our units these temps are accurate to 0.5ºF degrees and are calibrated to NIST standards.
View our selection of automatic reset switches. You can also give us a call at 715-831-6353 or email us for more information or to request a quote.
Automatic Reset Snap Disc Thermostats
This type of control can be built to either open or close its electrical contacts as the temperature increases. Once the temperature of the bimetal disc has returned to the specified reset temperature, the contacts will automatically return to their original state. 
Our heavy duty 25 Amp automatic reset thermostat switch is great for unique applications which require a faster response time or a lower contact resistance. The 15 Amp auto reset switches are available in many different mounting options and create a small footprint being a more cost effective solution.
The below options have a switching temperature range of 0-350°F. If you require a hotter temperature of 350°F-450°F, our ceramic style thermostat switches will be best for your application.
To view more information our automatic reset thermostat switches, click here.
