Indeed. We had proper ground fault protection breaks for that purpose, and it was really hard to get them.
That + the use of metal tubing to carry electrical power as well as the incredibly flimsy construction of various sockets and such (as well as the high amperage) translates into lots of preventable fires each year in the USA and Canada. Point a FLIR at your average distribution panel and try not to be amazed at the number of hot spots.
My biggest gripe: I don't mind inspectors, I just expect them to be really knowledgeable, not just theoretical. Grounding a structure is inherently different from grounding a circuit. He basically kept on insisting that the windmill is part of the circuit and should be bonded rather than that it had its own ground and that is just patent nonsense, more so because the windmill produced variable frequency AC that first had to be rectified, passed through a battery charger, a bunch of batteries and an inverter. The latter of course was bonded to the house ground.
Outside is another matter. Those galvanized steel tubes don’t last very long underground, and the results are terrifying. And nothing in the code requires ground fault protection upstream of a 120V circuit running through a corroded steel tube underground.
They conduct electricity. Thus if you have a leak from one conductor somewhere in your house (that without ground fault protection goes undetected almost every case) and gets a different one from a different wire, you now have a constant-on heater passing through God knows where, ready to start fires.
A single leak also gives you a minor risk of electrocution. But the fire hazard is the important one.
This is possible with nonmetallic conduit, too, as well as with NM-B. At least metallic conduit has a decent chance of containing the resulting mess inside the conduit.
The right solution is ground and arc fault protection, both of which are available, and one of which is increasingly required in the US.
You seem to be thinking about short circuits. That's not what my post is about. (Anyway, plastic conduits are quite capable of containing the mess.)
And yes, they are way less dangerous if you have ground fault protection. To the point that I'm not sure it's still important to ban them. But they don't have any upside either.
I think metal conduits are most useful in more industrial-ish spaces where they're exposed -- they're quite resistant to getting banged up. Schedule 80 PVC works, too, but it's harder to work with than steel (at least for an electrician with the right tools).
That + the use of metal tubing to carry electrical power as well as the incredibly flimsy construction of various sockets and such (as well as the high amperage) translates into lots of preventable fires each year in the USA and Canada. Point a FLIR at your average distribution panel and try not to be amazed at the number of hot spots.
My biggest gripe: I don't mind inspectors, I just expect them to be really knowledgeable, not just theoretical. Grounding a structure is inherently different from grounding a circuit. He basically kept on insisting that the windmill is part of the circuit and should be bonded rather than that it had its own ground and that is just patent nonsense, more so because the windmill produced variable frequency AC that first had to be rectified, passed through a battery charger, a bunch of batteries and an inverter. The latter of course was bonded to the house ground.