Thermal Protection

ATC Semitec stocks an extensive range of auto-reset, manual reset and self-hold thermal protection devices from some of the world’s leading manufacturers such as PEPI, ASAHI, SEFUSE, EAW and SEKI.

Thermal protectors are used as safety mechanisms which will protect your products from overheating in the result of an abnormal operating condition.  The thermal cut-outs will protect against an over-temperature situation which could ultimately help to prevent fires or major damage to electrical components or appliances.

Typically thermal protection devices can be split into 2 categories:

  • Thermal Cut-outs
  • Thermal Fuses

A thermal cut-out (or thermal limiter or thermal switch) is a resettable thermal protection device.  They are available in either probe-style or 1/2″disc formats and can offer auto-reset, manual-reset or self-hold (remote reset) functions.  ATC stocks a wide range from PEPI, ASAHI & SEKI and these cut-outs help to protect products against abnormal operating conditions caused by overload, high ambients or primary control failure.

Asahi US-603 Manual Reset 1/2" Disc ThermostatThe typical application of a thermal cut-out is to stop a temperature from exceeding a particular threshold during overload conditions.  It normally opens at a high temperature during a fault condition and then resets when the product temperature is at a safe level.  Auto-reset, manual-reset and self-hold reset functions help to give different levels of protection.  Thermal cut-outs help to protect small appliances, large appliances, electric motors, heating elements and battery packs.

A thermal fuse (or thermal cut-off or TCO) is a one-shot, non-resettable, temperature-sensitive device that provides ultimate temperature protection in small appliances, battery packs and electronic circuits.  Thermal fuses cannot be reset or repaired, they have to be replaced once the original fault (that caused them to fail) has been rectified.

Thermal fuses are fail-safe devices which activate when other safety measures fail to operate, therefore preventing temperatures rising to dangerous levels, and will help to prevent fires. This could either be due to malfunction or misuse.  One-shot thermal fuses (thermal cut-offs or tcos) are defined by their temperature setting and also by their current rating, i.e. the maximum continuous current that can be applied.

Their typical applications include for use in rechargeable batteries, small electric motors, transformers, heating elements and domestic appliances.

We stock a wide range of SEFUSE pellet fuses up to 240°C and supply PEPI bimetal thermal fuses up to 280°C  – these bimetal fuses offer the ultimate in high temperature protection when pellet fuses can be less reliable.

Use our helpful guide to help you match the best PEPI thermostat to your application – click here

Call us today on 01606 871680 or complete the Contact us form, to discuss your application’s thermal sensor requirements.  Using our extensive technical knowledge and innovative supplier base, we will work with you to provide the optimum solution for your product.

Please also take a look at our downloadable ‘how-to’ guide to thermal controls. Refreshes your knowledge and gives great advice regarding choosing optimum applications for working with bimetallic devices and tips on improving their performance.