Principle of ACB Air Circuit Breaker

There are 3 ways of tripping: thermal, electromagnetic and compound tripping.

When the line has general overload, the overload current can not cause the action of the electromagnetic tripping device, but it can make the heat element produce certain heat, promote the heat of the double metal sheet to bend upward, push the lever to disconnect the hook and lock, break the main contact and cut off the power supply. When the circuit has short circuit or serious overload current, the short circuit current exceeds the instantaneous release current value, the electromagnetic tripping device produces enough suction, and the armature is absorbed by the impact lever, so the hook is rotated upwards and the lock buckle is disconnected. The lock buckle divides the three main contacts and cut off the power supply.

The release mechanism of the switch is a set of connecting rod devices. When the main contact is closed through the operation mechanism, the lock is locked in the closing position. If a fault occurs in the circuit, the related tripper will work to disconnect the lock hook in the release mechanism, and the main contact is quickly broken off with the release of the spring. According to the different protection functions, release can be divided into over current release and pressure relief release.


The effect of ACB Air Circuit Breaker
ACB Air Circuit Breaker is a very important electrical apparatus in low voltage distribution network and electric drive system. Universal circuit breaker has many functions of control and protection. In addition to the ability to complete the contact and split circuit, universal circuit breaker is able to protect the circuit or electrical equipment from short circuit, serious overload and undervoltage, and can also be used to start the motor infrequently.

Under normal conditions, the armature of the overcurrent release is released; in case of serious overload or short circuit fault, the coil in series with the main circuit will produce strong electromagnetic suction to draw the armature down and open the lock hook to disconnect the main contact. Undervoltage tripping device of the work on the contrary, the voltage is normal, the electromagnetic suction armature, the main contact is closed. Once the voltage drops or the power is cut off, the armature is released and the main contact is disconnected. When the supply voltage is restored to normal, universal circuit breaker must work again after reclosing, achieving the loss of voltage protection.

Because there are many ways of insulation, such as oil switches, vacuum switches and other inert gases (six sulfur fluoride gas) switch. The air switch uses air to extinguish the arc generated during the switch. So it's called air switch.