Electrical circuit installed thermal relay, not to install circuit breakers, isolating switch instead?

Publish Time:2017-06-15 Author:admin Views:0

The function of the thermal relay is to cut off the power automatically when the motor is over load, and the structure of the thermal relay is composed of two pieces of metal with different expansion coefficients, the expansion coefficient of which is large when the current is too large, and the effect of cutting off the power supply. The thermal relay is manually reset and automatically reset after operation.

The thermal relay needs to be used in conjunction with the AC contactor to disconnect the control circuit from the contact point on the thermal relay during overload.

No circuit breaker to the isolation switch can also be, but if the control loop current is large, directly cut off the isolation switch has arc, generally used for small load. The circuit breakers cannot be replaced with the isolation switch, because their functions are different. The best circuit breaker, normally connected and disconnected in the circuit of no-load and load current, in the system failure can be with the protection device and automatic device on weekdays, and quickly cut off the ancient costume current, to prevent the expansion of the accident, so as to ensure the safe operation of the system!

Electrical circuits have at least two types of short-circuit and overload protection.

Thermal relay is a component of overload protection, no short-circuit protection function, and choosing suitable circuit breaker can play overload protection function.

Electrical circuits have at least short circuit and overload protection, the general domestic equipment is the thermal relay directly connected to the circuit breaker. In fact, imported equipment by a lot of Siemens type of space to replace the two.