Designer69
Senior Member
I never really brushed up on megger testing of control wiring and don't know much about it.
We do an insulation test on everything.
As a rule of thumb it is twice operating voltage plus 1kV.
I never really brushed up on megger testing of control wiring and don't know much about it.
Note of caution, you can easily cook electronic controls doing this so you have to knwo what you are testing.
Per ANSI and NETA specs"Perform insulation-resistance tests on all control wiring with respect to ground. Applied potential shall be 500 volts dc for 300 volt rated cable and 1000 volts dc for 600 volt rated cable. Test duration shall be one minute."
And..."Insulation-resistance values for control wiring shall be a minimum of 2.0 megohms."
Could you direct me to your source,or maybe site a section or article #, somthing I could present to my foreman.
I have been told that we(my boss) do(es) not meg our 600v wire at 1000v because it is in excess of the insulation rating.
Isn't is true that there should be no electrical/electronic components connected to the wiring that is to be megger tested?.
The only time I meg is for troubleshooting purposes or for PM schedule on motors. I never understood megging new low voltage installs.