I saw one of the clearest examples of a dead short that I have ever seen. The outdoor pop machine was daid to the world, so my Dad (of course) sicced me on it. Every time I threw the breaker for the exterior outlet when the machine was plugged in resulted in an immediate trip. Nothing plugged in, no trip. Fan plugged in worked just fine.
Went to Ace for a right angle plug, went back to the rifle club and started to dissect the original plug. Didn't take long, as soon as I pulled the outer sheath back, I saw where the hot, neutral, and ground conductors were bare. Hot n neutral conductors had welded about half their strands...
Opened the replacement plug and prepped it for attachment, and I found out that the insulation on ALL three wires was brittle. Couldn't strip the sheath back far enough to find good insulation, so after a foot, I gave up. As soon as the fiber packing material was stripped from the conductors, the insulation started to crack.
Told my Dad that the cord needed to be replaced.