Getting a motor wet

[macmet]

Hello Everyone,

I was just on site last week looking at one of our systems that had been delivered recently. One of the pieces was a screw conveyor/trough with the gearmotor mounted on it. The gearmotor had been wrapped with the intention of keeping it clean and dry but when I peeled off the wrap a lot of water poured out.

Will this water potentially cause damage to the motor? Will it be alright if it airs out? Should it be replaced? The unit itself is not wired and will not be wired for a couple months still.

It is a TEFC motor. 460V/3Ph/60Hz. Not sure if any other information may help.

 

[MintJulep]

Will it potentially cause damage? Yes.

Will it be alright if it airs out? Maybe.

Should it be replaced? Yes.

 

[Artisi]

The motor should be removed and stator and rotor and housing dried-out, the bearings should also be removed and depending on type either re-greased or replaced.

 

[bklauba]

Certainly replacing the motor is the safe way to go. Alternatively, the motor could be allowed to dry out (perhaps), electrically isolated and "meggered" to see if moisture is compromising the insulation.

If found that the megger reading is unacceptably too low (the motor manufacturer would have an idea of what that would be, and best to get their input here), then the motor could be removed, partially disassembled, and the stator baked out to remove the moisture, and reassembled. This should be done with care, so as to avoid damage to bearings and the stator (which should be removed). A good motor shop should be able to perform these services.

This is not, unfortunately, an uncommon occurance. For the reasons outlined, or finding that a dyanmic balance of a motor was not done (well enough, or at all?; certain brands are notoriously out-of-balance), many motor shops do a careful tear-down and corrective work for the reasons outlined, or adding "heaters", RTD's, etc.

BK

 

[JamesBarlow]

Being a TEFC motor I would talk with the motor company first.

Some motors are better sealed than others so you may not have any concerns but it depends on how much water and for how long. Since the motor was not wired one point of concern would be water getting in the the peckerhead. Sometimes this is sealed, and sometimes not depending on the manufacturer. Again, talk with the manufacture directly about what happened. They will be the experts on their motor.

If there is any concern that water got into the motor then just pull it. You have plenty of time to either buy a new one or have the current one rebuilt. What's the cost of being wrong and having the motor fail versus the cost of having it rebuilt? Answering that question should tell you what to do next.