A relay is an electrical appliance that switches on or off the control circuit to complete control or protection tasks based on signals input from outside, such as electrical quantities (voltage, current) or non-electrical quantities (heat, time, speed, etc.). There are three basic parts, namely the sensing mechanism, the intermediate mechanism and the actuator. The article describes the troubleshooting methods for their failure.
1.Coil troubleshooting
The coil fault is usually damaged by coil insulation; short circuit or grounding is formed by mechanical damage; because the power supply voltage is too low, the contact between the moving and static iron core is not tight, so that the current passing through the coil is too large, and the coil heats up and burns. When repairing, rewind the coil. If the armature does not pull in after the coil is energized, it may be that the coil lead-out line is disconnected, causing the coil to open. Check the drop off and solder it.
2.Core troubleshooting
The iron core failure mainly has the armature that cannot be sucked up after being energized. This may be caused by a broken wire, a foreign object between the moving and static iron cores, and a low power supply voltage. Repair should be done differently.
3.The thermal element burned out.
This may be due to a short circuit on the load side or a high frequency of operation of the thermal element. The heating element should be replaced during maintenance and the setting value should be readjusted.
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