Induction Motor Condensation 1

[microaid]

I am trying to understand a problem that was explained to me in rather vague terms concerning condensation in electrical induction motors operating in a refrigerated room (15deg C). I understand the motors run continuously, 3x8hr shifts, and are sealed units (would this be correct?) but require high maintenance due to damage from condensation. Wouldn't condensation only be able to form inside the motor when they are off line, and if they are sealed units wouldn't there be a limit to how much moisture could be condensed from the air inside the motor.
Are the standard methods of controlling condensation which are discussed in existing threads applicable here?
My thanks to all for your willingness to share your time and experience.

 

[jbartos]

Suggestion: The condensation in the motor may also be dependent on the moisture in the air. However, if the motor is sealed, or waterproof, then there is no condensation inside. See submersible pump motors, for example.

 

[jraef]

I agree, if they truly are sealed condenser motors. They are sealed for that exact reason.

If not, are you sure that the motors run continuously? Just because the circuit is on all the time does not necessarilly mean that the motors are running. Depending on the design, they may be coming on / off several times a day as the system becomes satisfied. In an environment that cold they will cool off quickly and condensation could form.

Thats a stretch though. Usually a refrigerated environment is not the place you want to locate a hot motor. Something sounds a little strange.

Quando Omni Flunkus Moritati

 

[smms]

I agree with jraef,
if you do not have an sealed motor with absolute dry air inside, water will always condensate if the motor stoppr running and if the housing is cooled from outside. You can avoid this problem by drying the winding up before closing the motor (in every insulation material you have some amounts of humidity).