Electric Motor Winding Tester

While testing make sure the leads on each end are not touching other leads or anything else.

Electric motor winding tester.

Bearing problems may be the number one cause of electric motor failure but electrical faults are a close second. Set the voltage level of the insulation resistance tester to 500v. Test t1 to t2 t2 to t3 and t1 to t3. Dc voltage of 500 or 1000 v is applied between the windings and the ground of the motor.

Technicians should perform a series of tests on an electric motor during routine preventive maintenance or before replacing it. This includes testing the motor for grounded windings. We ll start with a quick review of why testing is important followed by a discussion of rotor bar hipot surge and motor winding resistance as well as a discussion of vibration analysis. If windings are shorted together the electro magnetic fields cannot be created for that coil causing the motor to run erratically or fail all together.

The megger will help to detect areas of deteriorating insulation where the windings may soon short. U v w is a european winding designation. If the winding s insulation wears away near the motor s case the bare wire winding shorts to ground. Ground insulation test of a motor.

You may find that when it runs ungrounded that the casing becomes live at up to supply voltage. How to test your spindle motor for open or short in windings. This should allow you to isolate your problem. With a multimeter set to low ohms usually 200 test between each winding terminal and the metal casing of the motor.

Often it is required to test the winding of the 3 phase windings with the aid of a multimeter or ohmmeter to determine whether the motor is still good or burnt or shorted. Remember that the three phases have identical windings or. Ac motor winding resistance test check the motor winding resistance or ohms reading using a multimeter or ohmmeter for phase to phase terminal u to v v to w w to u the ohms reading for each winding must be the same or nearly the same. If there is any reading on any of these then the motor is bad do not use it.

Most repair shops will use a megger or a ground insulation tester. During the measurement and immediately afterwards some of the terminals carry dangerous voltages and must not be touched. The most common failure mode of a 3 phase ac motor is burnt winding or shorted winding leading to the damage of the motor. The measurement of insulation resistance is carried out by means of a megohmmeter high resistance range ohmmeter this is how the test works.

Set your multimeter to ohms.