Pouring water on an Induction Motor may stop it working, due to the lowering of the insulation resistance of the internal motor coil windings.

The coil windings are located inside the metal case of the induction motor, and are what generates a magnetic field, which makes the motor turn.

This article will focus on what are known as ‘three phase’ Induction Motors, which have three sets of coil windings inside the motor.

Therefore the Stator contains three sets of coil windings.

The internal motor windings are wound together in a component known as a ‘Stator’.

Each winding is electrically separated by an insulation layer on the copper wire that makes up a stator winding.

Therefore there should be a high level of electrical resistance between each of the three coils.

This ‘Insulation Resistance‘ is typically above 2 Mega Ohms in a correctly operating Induction Motor.

However if the coil windings became wet, then the insulation resistance would drop to a low level, which would prevent the motor from operating, due to a short circuit between the coil windings.

The good news is that induction motors can usually be dried out, and therefore returned to having a high insulation resistance between the Stator coils.

Drying out the stator coils can be done with gentle heating methods.

It is of course vital that the motor is disconnected from the electricity supply, and that only a qualified person carries out the work.

One method is to remove the Rotor from the motor casing, to allow easy access to the Stator.

Once the Rotor has been removed, the wet stator coils can be air dried.

Applying warm air from a hairdryer can help, but don’t overheat the coils, as this could damage them.

A warm oven on a very low heat is another possibility, but only use minimum heat, and not for too long.

Do NOT use a microwave oven, this will cause sparks and damage to the microwave. This is due to the motors metal case.

Another option for drying the stator windings, is to use an electric welding set.

The set is connected on low power to the coil terminal ends, and switched on.

This gently heats up the winding in a similar way to an electric heater element. Therefore drying the stator.

These methods are only suggestions, and for educational purposes. I accept no liability for your injury, loss or damage.

@acraigmiles

Published by Craig Miles

Craig Miles