How Do You Test An Electric Motor With A Multimeter

Do the following with the motor disconnected.

How do you test an electric motor with a multimeter.

Turn on the multimeter. The megger will help to detect areas of deteriorating insulation where the windings may soon short. Most repair shops will use a megger or a ground insulation tester. In the ohmmeter mode connect the meter to the plug and monitor the resistance as you wiggle the cord where it enters the enclosure.

You may find that when it runs ungrounded that the casing becomes live at up to supply voltage. Since there are three terminals s c r in a single phase motor measure winding resistance. With a multimeter set to low ohms usually 200 test between each winding terminal and the metal casing of the motor. Small universal motors as for portable electric drills may contain extensive circuitry including a switch and brushes.

The most common failure mode of a 3 phase ac motor is burnt winding or shorted winding leading to the damage of the motor. Measured value s to r should be c to s c to r. 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. Ac motor winding resistance test check the motor winding resistance or ohms reading with a multimeter.

Values measured in this phase of testing should be around fifteen ohms. Test for direct shorts in the motor s power windings in induction non brush type motors. In this video we show different tests balancing test continuity coil. Ensure it is set to measure volts as multimeters.

If there is any reading on any of these then the motor is bad do not use it. You need to check if electricity is getting to the motor. Keep the multi meter set for 30 000 ohms and touch one test lead to one terminal and the other to another terminal. You will now place the red probe on the common wire.

When an electric motor is broken one suspect is the fiel coild of the motor stator. C to s c to r and s to r. Test the fourth set of wires. For generally testing of induction motor we perform three test 1 continuity test 2 short circuit test ground test in continuity test we the resistance of the.

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.