(1) Check new items in operation.

1) According to whether the load current is within the rated current of AC contactor.

2) Whether the opening and closing data signal of AC contactor is consistent with the circuit state.

3) Is the operation sound normal? Is there any charging and discharging sound due to poor contact.

4) Whether the electromagnetic induction coil is overheated, and whether the short circuit fault ring of the electromagnetic coil is abnormal.

5) Whether the arc extinguishing cover is loose or damaged.

6) Whether the auxiliary contact is ablated.

7) Is there any damage to the transmission system.

8) Does the surrounding software environment have factors that are not easy to operate, such as excessive vibration, poor natural ventilation, too much floating dust, etc.

(2) Maintenance. During the maintenance of electrical equipment, the AC contactor should be maintained at the same time.

1) External maintenance.

① Clean up the outside dust.

② Check whether the standard parts are loose, especially a part of the electrical conductor connection, to avoid touching loose and hot.

2) Maintenance of contact point system software.

① Check whether the dynamic and static contact parts are aligned, and whether the three phases are closed separately. If not, adjust the contact point spring yellow.

② Check the damage level of the contact point. The damage depth should not exceed mm. If the contact point is ablated, it needs to be replaced immediately when it falls off the welding. If it is slightly ablated, it generally does not endanger the application. It is not allowed to use sandpaper when cleaning the contact point, but a plastic file should be used.

③ Accurately measure the grounding resistance of two colors, and the resistance value shall not be less than 10m Ω.

④ Check whether the posture of the auxiliary contact is flexible, the travel arrangement of the contact point should meet the standard value, and check whether the contact point is loose. If any problem is found, repair or replace it immediately.

3) Maintenance of part of the core.

① Clean up the dust, especially between the fitness exercise components and the core suction surface.

② Check the tightening condition of the iron core. Loose iron core will increase the operation noise.

③ If the iron core short circuit fault ring falls or breaks, it should be repaired immediately.

4) Electromagnetic induction coil maintenance.

① Accurately measure the grounding resistance of the coil.

② Whether the coil insulation has discoloration and embrittlement, and the coil surface temperature shall not exceed 65 ℃.

③ Check the connection of coil wire, and repair immediately in case of open welding and ablation.

5) Maintenance of arc extinguishing hood.

① Check whether the arc extinguishing cover is damaged.

② Whether the arc extinguishing hood is loose or changed.

③ Eliminate metal particles and dirt in the gap of arc extinguishing hood.

Analysis of common problems of AC contactor

1. Reclosing is not allowed after power supply is connected

(1) Check if there is a short circuit in the coil power supply system, and connect the broken point again.

(2) Check whether the contact of the start button is in poor contact.

(3) Check whether the rated current of the coil is higher than the working voltage of the coil, and replace the coil with suitable rated current.

(4) Check whether the contact is stuck between the contact and the wall of the arc extinguishing chamber, or whether the sliding rail or guide groove between other moving parts is stuck.

(5) Check whether the transmission shaft is rusted or tilted, remove it and clean it for rust prevention, or replace the damaged parts and grease them.

(6) Check whether the power supply voltage of the control circuit is too low, and adjust the power supply voltage.

(7) Check whether the working pressure of the released spring yellow is too high, and adjust it.

(8) Check whether the contact stroke is too large and adjust it.

2. Excessive noise or vibration during operation

(1) Check whether the coil working voltage is not enough, and adjust the coil working voltage.

(2) Check whether the total area of the core pole is stained, rusted or uneven due to excessive damage. Remove the pole surface and repair it if necessary.

(3) Check whether the short circuit fault ring is broken, and replace it with a new one.

(4) Check whether the clamping screw of moving and static iron core is loose, and tighten the screw.

(5) Check whether the mobile parts are not well coordinated with each other, and carry out adjustment after finding out common faults.

(6) Check if the recoil is too large.

3. Release the start button and the AC contactor will be released immediately

(1) Check whether the auxiliary contact of AC contactor is in poor contact. Remove the auxiliary contact or replace it with a new one.

(2) Check whether the contact in the control circuit is in bad contact, and find out the contact in bad contact, and replace or remove it in many aspects.

(3) Check whether the wiring of locking contact is wrong.

4. The posture of AC contactor is too slow

(1) Check whether the gap between the moving and static iron cores is too large, and adjust part of the mechanical equipment to reduce the gap.

(2) Check whether the installation position is not secure, and replace it again according to the product manual or technical standards.

(3) Check whether the coil working voltage is not enough, and adjust the coil working voltage.

(4) Check if the recoil is too large.

5. The AC contactor cannot be released after the power is turned off

(1) Check whether the recoil spring yellow is too small, and replace the appropriate spring yellow.

(2) Check whether the magnetic loss is too large. For DC contactor, replace or thicken the non-magnetic gasket

When communicating with the software of AC magnetic system, a part of the polar surface of the magnetic loss gap should be filed off or the magnetic system software should be replaced.

(3) Check if the glycerin on the surface of the core of the new AC contactor is not cleaned.

(4) Check if the moving part is stuck.

(5) Check whether the installation position of AC contactor is stable.

(6) Check whether the contacts are arc welded together, break the arc welded contacts or replace them with new ones.

(7) Check whether there is a mistake in the routing of the control route, and check the route again.

6. The coil of AC contactor is damaged or the lead is broken

(1) Check whether the coil insulation is damaged due to damp cold gas or corrosive vapor.

(2) Check if the inside of the coil is disconnected. If it is disconnected, replace it with a new coil.

(3) Check whether the AC contactor is damaged by impact or vibration.

(4) Check whether the coil rated current is lower than the control circuit.

(5) Check whether the power continuity rate of the coil is inconsistent with the specific situation.

(6) Check whether the coil operates beyond the required working voltage.

(7) Check whether the AC contactor operates under working voltage and whether the streamline coil can not be closed.

(8) Whether the actual operating frequency of AC coil is too high.

(9) Check whether the double coil structure is connected to the power supply for a long time due to the welding of the locking contact and the starting of the winding.

(10) Check whether the working temperature around the AC contactor is too high.

(11) Check whether there is short circuit fault between turns of AC contactor coil.

(12) Check whether the coil of AC contactor has local short circuit due to mechanical equipment damage or conductive floating dust.

(13) Check whether the electric welding of the connector of AC contactor is not good, so that it is damaged due to the excessive resistance of the circuit.

(14) Check whether the coil current of AC contactor is too large and adjust it.

7. Check whether the contact of AC contactor is seriously hot

(1) Check whether the load current is too large.

(2) Check whether the contact is seriously rusted, or there is too much dust, or the copper contact has been seriously oxidized by air.

(3) Check whether the contact stroke of AC contactor is too small, adjust it if it can be adjusted, and replace it if it can not be adjusted.

(4) Check if the contact pressure is not enough.

(5) Check for loose wiring.

8. Arc welding of main contact of AC contactor

(1) Check whether the vibration is too strong in the whole process of closing and closing, and whether it is caused by too high working voltage of power supply system.

(2) Check if the contact pressure is not enough.

(3) Check whether the breaking capacity of contact is not enough.

(4)Check whether there are metal particles or dirt on the surface of the contact.