Maintenance of AC contactors is generally divided into operation inspection and stop maintenance.

I. In the operation of equipment, AC Household Contactor need to be inspected as follows:

1. Whether the load current passed is within the rated current range of the AC contactor;
2. Whether the dividing and closing indication signal of AC contactor is in conformity with the normal working state of the circuit;
3. Whether the sound of AC contactor is normal in operation, whether there is noise or discharging sound due to bad contact;
4. Whether the electromagnetic coil of AC contactor is overheated or not, and whether the short-circuit loop of the electromagnet is normal.
5. Whether the arc extinguishing cover of AC contactor is loosened or damaged;
6. Whether the auxiliary contacts of AC contactors are burned or not;
7. Whether the transmission part of AC contactor is damaged or not;
8. Whether the operating environment around AC contactor exists unfavorable factors to the operation of AC contactor, such as excessive vibration, poor heat dissipation environment, excessive dust and so on.

II. Maintenance of AC contactor in non-working state:

If the electrical equipment stops working and needs maintenance, it is necessary to maintain the AC Household Contactor at the same time.

1. External maintenance of AC contactors:
1) Cleaning the external dust of AC contactor;
2) Check whether the fasteners on AC contactors are loosened, especially the connection parts of important conductors, so as to avoid heating of AC contactors due to the loose contact of conductors.

2. Maintenance of AC contactor contact system:
1) Check carefully whether the dynamic and static contact positions of AC Din Rail Mounted Contactor are correct and whether the three phases are closed in place synchronously. If there is any problem, the contact springs of AC contactors can be adjusted by adjusting.
2) Carefully check the contact wear of AC contactor, the wear depth should not exceed 1mm. If the contact of AC contactor is burnt and the silver contact is falling off, the AC contactor must be replaced in time. If it is slightly burnt, it will not affect the use of AC contactor in general. Particular attention should be paid to the prohibition of sandpaper when cleaning contacts of AC contactors, and plastic files must be used to clean contact surfaces.
3) Strictly measure the inter-phase insulation resistance of AC contactors, and the resistance value is not less than 10M.
4) Check carefully whether the auxiliary contacts of AC contactors are flexible in action, whether the contact stroke meets the required value, check whether the auxiliary contacts are loose and fall off. If problems are found, the auxiliary contacts should be repaired or replaced in time.

3. Maintenance of iron core of AC Household Contactor:
1) Cleaning dust, especially between the moving parts of AC contactor and the contact surface of iron core.
2) Carefully check the tightening condition and rust stain of AC contactor core. Loose or rusty iron core will cause the noise of AC contactor to increase.
3) If the iron core short-circuit ring of AC contactor falls off or breaks, it should be replaced or repaired in time.

4. Maintenance of electromagnetic coils of AC contactors:
1) Measure the coil insulation resistance of AC Din Rail Mounted Contactor carefully;
2) Check the coil insulation of AC contactor for discoloration, aging and other phenomena. The surface temperature of coil should not exceed 65 degrees C.
3) Carefully check whether the coil lead connection of AC contactor is open-welded or burned, and if so, it must be repaired in time.

5. Maintenance of arc extinguishing cover of AC contactor:
1) Check carefully whether the arc extinguishing cover of AC Din Rail Mounted Contactor is damaged or not, and if so, replace the arc extinguishing cover.
2) Check whether the position of the arc extinguishing hood is correct, whether there is loosening or position change;
3) Carefully remove metal particles and impurities in the gap of AC contactor arc extinguishing hood, and keep the gap clean.