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Question:

How do I test an AC single phase electric motor with a meter to see if it is burnt?

How do I test an AC single phase electric motor with a meter to see if it is burnt?

Answer:

Ideally you need a megger but you may detect a fault with a multimeter but it will only tell you if its bad not if its definitely good. A single phase motor has 2 windings. Test each one (any wire) to ground. You should have a very high reading (many millions of ohms). You should then be able to test a circuit through each winding but not much way of knowing the resistance unless you have an identical motor to check against. If it has a contact to open the start winding, then this should be checked (closed stopped) as it is a common fault and easy to test. If it has a capacitor then try replacing it.
Single Phase Motor Winding Checking
With a megger tester, check the motor insulation resistance, line to ground. If its resistance is almost zero, the motor is possibly overheated or burnt. With a volt-ohm multitester, check the motor resistance from one line to another. Its resistance should be from 1 to 3-ohms only. If its resistance is above 100,000 ohms, its windings may be open. Also, check for a burnt smell. A burnt motor usually smells burnt enamel wire.

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