How Do You Test Electric Motor Windings

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.

How do you test electric motor windings. Check that the correct voltage is applied to the motor. Dc voltage of 500 or 1000 v is applied between the windings and the ground of the motor. Ac motor winding resistance test check the motor winding resistance or ohms reading with a multimeter. Keep the multi meter set for 30 000 ohms and touch one test lead to one terminal and the other to another terminal.

Test for direct shorts in the motor s power windings in induction non brush type motors. If there is any reading on any of these then the motor is bad do not use it. The most common failure mode of a 3 phase ac motor is burnt winding or shorted winding leading to the damage of the motor. Small universal motors as for portable electric drills may.

With a multimeter set to low ohms usually 200 test between each winding terminal and the metal casing of the motor. During the measurement and immediately afterwards some of the terminals carry dangerous voltages and must not be touched. Each of the sets of windings should read about the same ohms value. Since there are three terminals.

Ground insulation test of a motor. For proper motor operation all windings must have megohm readings to ground i e. If you have access to a multimeter it s easy to determine if you have an immediate problem. Sounds like you have a winding down to ground.

Do the following with the motor disconnected. To the motor enclosure. Here is a basic breakdown on how to check motor windings with a multimeter keep in mind this is just a quick way to determine if your motor is in need of further. 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.

Test electric motor windings when a bad motor winding cannot be found by a physical inspection many times an ohmmeter may show that there is a defective winding. Most repair shops will use a megger or a ground insulation tester. If you think you may have bad spindle motor windings it s important to know for sure. Armature test 1 to check the condition of the armature windings the armature will probably have to be removed from the motor.

Power supply test for single phase motors the expected voltage is about 230v or 208v depending whether you are using the uk or america voltage system.