How to choose a circuit breaker, when choosing a circuit breaker, pay attention to the seven major functions, consider the seven factors, and understand the seven common functions that should be paid attention to when choosing a circuit breaker.

Common functions of circuit breakers:

1. Duplex control (remote trip or relay trip).

The multiple control circuit breaker combines two inductive elements electrically isolated from each other to achieve multiple functions. For example, remote control actuators or sensors can be used for traditional overcurrent protection and circuit disconnection.

2. Low voltage trip.

This is an independent voltage sensitive component in the circuit breaker. If the voltage drops below the predetermined value, it will open the main contact. Switching circuit breakers with low voltage trips are widely used for on/off control of wired connected electrical appliances.

3. Automatic tripping.

In a fully automatic trip design, when the actuator is held in the “on” position, the circuit breaker will periodically switch on and off.

4. Auxiliary contact (auxiliary switch).

They are contacts that are electrically isolated from the main contacts and are suitable for alarms and program switches. In addition to being used for alarms, it can also be used for backup power in important applications.

5. Transmission.

A drive rocker switch circuit breaker with a switching speed twice that of an on/off switch can save costs and circuit board space; push-pull actuators are the most stable in emergencies.

6. Shunt terminal.

Unlike traditional circuit breaker contacts, current sensing elements and loads that are all connected in series, the shunt terminal is branched from the main circuit to connect the secondary load.

If the primary load is short-circuited or overloaded, the circuit breaker will trip and cut off the power to the two loads.

Different from the auxiliary contact, the shunt terminal is connected to the circuit breaker located between the switch contact and the current sensing element, which means that the second load will not be protected from overload or short circuit, and an independent circuit breaker is required to protect the secondary circuit , Otherwise the circuit can only be used for equipment with built-in protection circuit.

7. Automatic reset.

For narrow spaces, a circuit breaker that automatically resets after a cooling period is suitable.

In short, the selection of circuit breakers must be specifically analyzed for specific situations to make it truly effective.