In an electric device, the high quality of insulation is an essential factor. There will certainly be transforms in the insulation property of electrical gadgets according to certain factors like eco-friendly conditions, temperature, time, etc. For this reason we require to examine the insulation resistance high quality at regular intervals so that we deserve to avoid electrical shock. A megger is provided to examine the insulation resistance of the electrical equipment. For this reason we have the right to use a megger to check a motor, generator winding, cable, etc. A megger test a wire by using a high voltage DC come it for a certain time duration so that the insulation quality deserve to be determined. A megger is made up of a DC generator and an Ohm meter.

How to usage a megger to check a three-phase motor
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Procedure

Before weuse a megger for trial and error we should check details factors

The leader in the megger need to be checked for any kind of faults. And also the leads should have electric continuity.To inspect the electric continuity of a megger we must attach both the leads together while the megger is ONCheck the dress wiring the the an equipment which is to be measuredMake certain that every the relations are complete before testing.

Check the three-phase motor is associated to delta or not, if so remove the links.

Windingresistance check of the motor

The first step would be checking the winding resistance. So prefer the multimeter a megger would also have a rotary selector so revolve it to Ohms and also after the check, the leads and also this will be checking electric continuity. Connect the probe come the motor to inspect the winding resistance from phase to phase terminal. So we must inspect the 2 ends the the first, second, and third winding, in bespeak to carry out this connect the probe come the an initial winding and also check its 2 ends through the various other probe and do the same for second and third winding. When doing this we must switch top top the megger testing. Throughout this testing all the windings must show high and almost equal worth then the engine is ok.

Insulationresistance check of the motor

In stimulate to execute this testing change, the megger setting to voltage and the voltage level need to be set greater 보다 250V. Attach one probe of the megger come the earth connection in the motor. For this reason insulation resistance to earth can be confirm then connect the 2nd probe to the an initial winding and also check the value, then carry out it because that the 2nd and third, and also if every the worths are virtually the very same then that is ok. Then examine the insulation resistance in between the windings.

While check the insulation resistance that the engine the values will be virtually the same for the three windings if therefore the engine is ok and also if the probes are associated to the very same winding then the meter will present zero.


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So if every the readings are nearly the same and also high for the insulation and also winding test of the motor climate the motor is ok.