The TR11 circuit breaker for equipment (CBE) is a single pole, push to reset, thermally operated overload protector, providing reliable trip free operation on overloads and short circuits within the maximum breaking capacity. The trip mechanism is of a latch type and a high contact force can be maintained until the unit trips.
This prevents contact bounce and reduces the risk of contact wielding. Main applications are protection of single-phase motor transformers, solenoids etc. against damage due to over current conditions.
The mechanism of the circuit breaker is designed to open the contacts in the event of a current flow in excess of the rated current according to the time/current characteristics of the device. A thermo bimetal strip, which has the advantage of being immune of high inrush currents and line transits, is heated by over current and deflects thereby releasing the latch mechanism.
The contacts open even if reset button is manually held in the closed position. The is known as trip free mechanism. The contacts open and close with a positive snap action and the tripped state is clearly indicated by the extended projection of the reset button.