Encapsulated motor windings

[eaglet]

Is anyone familiar with the navy's water test for encapsulated stators per Mil-m- 17060E. We have several large motors that we are having problems passing the resistance check.

 

[GusD]

Hello Eaglet

I am a little confused when you say that your motors are having a tough time to pass the resistance checks but yet you want to try the Navy's water test.
Perhaps I misunderstood your question.In any case I will
mention here the MG1-12.63 "conformance test" for moisture resistance windings or encapsolated windings.This test involves placing the motor for 168 hours in a Humidity chamber.This test is not a production test,but basically to test prototype insulations.
Check IEEE 429 on the specifics of the water test.
I am curious about what you mean when you say"Your motors
have a hard time passing the Resistance test".Is it a Megger test,ohmeter test,PI test etc,etc?Can you elaborate on that.

GusD

 

[eaglet]

The test that we are doing is a production test for insulation resistance. It involves submersing an encapsulated stator in a tank of water for 24 hours. We do a Meggar test at 1 hour and at 24 hours for ten minutes. We all so do one minute test every hour. If the reading falls below 100 megohms, the stator is considered to fail the test.