1. Application

BW-T Thermal Protector is an overheat protection device for single-phase motors under 250V due to overload, blocked rotor, and other abnormal operating conditions. Can also be used for heating appliances, fluorescent lamp ballasts, transformers, ICs, and general electrical equipment for overheat protection and temperature control.

   BW-T is a thermally operated snap-action & automatic reset device, which delivers the overheating and or overloading protection, widely used in single-phase motors under 250V. It can also be used as a thermal protector or temperature controller for heating appliance, ballast, transfers, etc.

2  Working Principle Operating principle 

BW-T Thermal Protector - Uses bimetallic strips of specific geometric shape as temperature-sensing elements. Through the strip's own temperature sensitivity, the bimetallic element rapidly changes state, driving contact pieces to automatically disconnect and reconnect circuits, providing overheat protection.

At the hart of the device is a bimetal snap-action disc. When the temperature of this pre-calibrated temperature, it snaps open, resulting in an open circuit. After the device breaks the circuit, the system cools down and automatically resets allowing power to be restored to the circuit

3Model Naming and Shape StructureDesignation and Dimensions

3.1 Model Designation

  BW－T     XXX

Opening Temperature

Iron Shell Metal case

Design Code Model Code

4.Contact CapacitanceMeasurement Contact Rating: 250V 1-6A