Insulation resistance check for a motor

[Ainsley Whyte]

I have a 40 HP motor 460VAC 3 PHASE NAME PLATE CURRENT IS 48 AMPS

I have done a insulation resistance test on it with a megger meter.

The voltage settings that i use for the megger check is 500 Volts

I am getting L1 - Ground 14 Megger ohms
L2 - Ground 14 Megger ohms
L3- Ground 15 Megger ohms
This is a new motor.

Are those readings acceptable

 

[tom baker]

Yes, but your readings are in mega ohms.
Megger is the trademarked name for an insulation resistance tester.
Try 1000 volts on your test

 

[macmikeman]

The gentleman is from Jamaica. Mega ohms might be megger ohm's where he is from.

 

[Ainsley Whyte]

Yes, but your readings are in mega ohms.
Megger is the trademarked name for an insulation resistance tester.
Try 1000 volts on your test

Thanks you are correct the readings are Mega ohms it was just my bad.
But you are saying that 14 M ohm, 15 M ohm and 14 M ohm are ok readings

 

[Ainsley Whyte]

The gentleman is from Jamaica. Mega ohms might be megger ohm's where he is from.

No I was incorrect it should be Mega ohms.
It should be 14 Mega ohm
15 Mega ohm
14 Mega ohm

 

[Jraef]

Insulation resistance value	Insulation level
5-10 Megohm	Abnormal
10-50 Megohm	Good
50-100 Megohm	Very good
100 Megohm or more	Excellent

If the motor is brand new out of the box, “good” is not what I would expect to see, but technically it meets the minimum standards.