You haven't been clear on your megger test procedure or your conduit layout. To begin, a megger test on new 600v cable, after installation, is usually required to be 100 meg or higher to be acceptable. That is from phase to phase, and phase to ground. What is your wire size? If a hole melted in conduit it must be a larger size, and you used an LB....bend radius!The insulation was stressed right there. Vertical drop on those conductors was how many feet? You state megger testing is only so good.....It's all you need if you know what you are doing....If the conductor melted a hole in the conduit you have more than a megger problem!duluthelectrical said:Thank you everyone for your comments, on one job the pipe got so hot at a point it melted a hole in it . Ground size and methods wasn't sufficient to clear the fault current. Other jobs I believe it was the feeding point, i.e at the lb conduit body. If jacket gets slightly nicked at conduit body then after sitting there contracting and expanding it finally meets its melting point and boom. Megger testing is only so good. Verticle dropping conductors need to be supported by conductor strain relief in future.