What is a Thermal Relay?Thermal relay definitionA thermal relay is defined as a device that uses unequal expansion rates of metals in a bimetallic strip to detect overcurrent conditions.Working principleThermal relays work by heating a bimetallic strip, causing it to bend and close the normally open contact, which triggers the circuit breaker.Construction of thermal relayIt consists of a bimetallic strip, metal with different expansion coefficients, a heating coil and contacts.Technical paramete