When to replace an ac contactor?

Q: AC contactor damage to what extent should be replaced?
A: (1) AC contactor three-phase main contacts (dynamic and static contacts burning area in more than 25%, the depth of loss in more than 1mm, the depth of loss in more than 1mm
(2) the contactor coil burned, the main contacts outside the terminal lined severe burns
(3) the main transmission mechanism of fracture or deformation of the contact, the contact can not be closed and blocked stuck
When the contact surface is caused by the contact surface of the contact surface, the contact surface is reduced. If it is a large power motor, it can be considered to start with decompression or frequency conversion, improve reliability
Replacement of AC contactor should be the first to buy the same parameters of the contactor, coil voltage, contactor capacity and model,
When the contactor can not be charged, the installation of screws and the time to pay attention to can not be lost in other electrical components to avoid a short circuit, if the condition is best to get a little bit magnetic, so that the screw can not be removed, and the best time to record the wire to avoid installing the wrong line,