Doug S. said:
There's still something missing here.
I never saw an answer about the type of megger being used. We have push button unit at work, and I HATE it, I don't trust it, especially on long runs. I'd trade my left pinky for the old hand crank I "grew up on". Does the reading change if the meter is left on over time? (Can you leave it on?) How about readings at 500v? ( We never meg over rated insulation value in house! ) If it's a hand crank does the feel of the crank change? How about DMM readings on the both sides of the cable, checking for voltage drop?
Good Luck,
Doug S.
PS Any one got a hand crank megger they want to get rid of? =)