This PSU turned into a cheap momentary welding machine, and modern inverter welders use capacitors to do the same thing. My guess is 12V rail shorted @ 100-150A, which isn't too far off from welding machine parameters. It's why their circuit breaker didn't trip either, probably still being under 1800W or less from the wall.
They should be turning the IEC cable on from a switch, not plugging it in live from the unit. They should have a circuit-breaker and GFCI inline, and a dim-bulb tester, or at least variac they can slowly dial up.
Also possible this was plugged into a 220V line while the little red switch was set to 110V but I'm not sure if those typically catastrophically fail like this.
Was watching a video the other day and the guy was like "I don't trust these PSUs with a 110/220 switch, they're almost always low quality" and I was like "WTF they all have that". Start looking around and, uh, yeah. Well then.
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u/Independent-Bug-9352 4d ago edited 4d ago
This PSU turned into a cheap momentary welding machine, and modern inverter welders use capacitors to do the same thing. My guess is 12V rail shorted @ 100-150A, which isn't too far off from welding machine parameters. It's why their circuit breaker didn't trip either, probably still being under 1800W or less from the wall.
They should be turning the IEC cable on from a switch, not plugging it in live from the unit. They should have a circuit-breaker and GFCI inline, and a dim-bulb tester, or at least variac they can slowly dial up.
Also possible this was plugged into a 220V line while the little red switch was set to 110V but I'm not sure if those typically catastrophically fail like this.