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Minimum insulation resistance on a 3 phase motor

frankmul · 2019-10-20 20:24:32

I thought the minimum value of insulation resistance in a 3 phase motor was 1 Mohm. I heard recently someone mention 2 Mohm. Would anyone be able to confirm which value is correct?

20-10-2019 09:24PM

#1

frankmul

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I thought the minimum value of insulation resistance in a 3 phase motor was 1 Mohm. I heard recently someone mention 2 Mohm. Would anyone be able to confirm which value is correct?

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Comments

#2 20-10-2019 09:37PM

2011

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To be honest it doesn’t really make any difference because for over 99.999% you will find that the resistance will fail by a country mile or it will pass by a country mile. You are highly unlikely to be a reading of between 1 and 2 Mohms.

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#3 20-10-2019 09:50PM

2011

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1 mega ohm is the minimum required. Test voltage 500 VDC

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