Motor Insulation Resistance Test

Loss of insulation resistance of an electric motor is one of the first signs of motor failure.

Motor insulation resistance test.

When performing insulation resistance testing you must maintain consistency. For a three phase motor insulation resistance is usually measured between each motor winding or phase and between each motor phase and motor frame earth using an insulation tester or megger. For a three phase motor the isolation resistance can usually be measured between each motor winding or phase and between each motor stage and motor frame earth by an insulation tester or megger 4. Basically there are three different tests that can be done using a megohmmeter.

The megger insulation tester is a small portable instrument that gives you a direct reading of insulation resistance in ohms or megohms. Because electrical insulation will exhibit dynamic behavior during the course of your test. The insulation keeps the current flowing along the wire exactly as intended. With a little record keeping and common sense however you can get a good picture of the insulation condition from values that are only relative.

Whether the dielectric is good or bad. Ground insulation test of a motor. Insulation resistance test insulation resistance failure of an electric motor is one of the first signs that the motor is about to fail. The measurement of insulation resistance is carried out by means of a megohmmeter high resistance range ohmmeter this is how the test works.

1 insulation resistance ir this is the simplest of the tests. Regular checks of motor insulation resistance the key to prolonging the life of any electrical device is periodic checks maintenance the insulation resistance of stored and active motors should be checked regularly. After 1 min you should read and record the resistance value. After the required connections are made you apply the test voltage for a period of one min.

Set the voltage. Insulation resistance decreases in temperature or moisture. Dc voltage of 500 or 1000 v is applied between the windings and the ground of the motor.