STEVETERRY
Well-Known Member
That won't blow a fuse unless there's one in the neutral for some reason. Harmonics only cause trouble for wire size and the supplying transformer.
There shouldn't be, but how do we know there actually wasn't? Maybe the installing electricians accidentally fused the neutral? It is said that something similar happened: a scrap of white tape caught on a wire that was being pulled in. This was, I believe, a service, so many large wires that are legal to re-code as white. Someone saw the white scrap, assumed it was supposed to be a neutral, and recoded said wire as a neutral. Someone (may or may not have been the same person) landed said wire on a phase lug...
I expect that made a bit of noise.
The NEC does not allow an overcurrent protective device in the neutral on a wye service. Typical three-phase wye switchgear would have no provision for a fuse in the neutral.
And actually, harmonics are a prime cause of overcurrent protective devices tripping or clearing "apparently" at current levels well below their rating.
However, "If you hear hoofbeats, don't suspect zebras."
There are many other plausible explanations to this situation--I hope to get to some of them if the OP answers my earlier questions.
ST