>>1555979A damaged power cord causing arcing on connection is damn unlikely, unless the psu-end plug is visibly completely ruined. The plug design makes it almost impossible for a *small* fault to cause this result.
>>1555988>Although my worries are more about the PSU blowing up or the rusted part causing a fire or something like that, rather than it just not working...The PSU committing sudoku if definitely possible, but if it's going to do that is already beyond rescue anyway. If it does that it will likely blow a capacitor or something, which looks and sounds dramatic but isn't actually dangerous.
Causing fire is a real risk. When there is actual arcing there is great heat development; there is nothing flammable enough in a PSU to cause fire *quickly*, but it might develop it if you try to ignore the problem and just run with it while it's making crispy sounds. It is a bit strange that you didn't end up blowing a circuit breaker, arcing in the plug is a sign of a short circuit and should definitely blow the breaker. But it could be arcing and a short circuit somewhere inside the PSU, which has a good of wrecking the PSU without triggering the breaker.
Another risk to consider is that a broken power supply might damage other components in your computer. This is not common when a power supply is visibly fucked; it tends to be a risk that applies more when a PSU is *subtly* about to give the ghost, not so much when it's visibly about to blow. But still, not a risk you want to take.
My recommendation is that you wait 24 hours (maybe moisture ended up in the PSU somewhere somehow), and then take your PSU out of your computer entirely. Plug it in somewhere far away, possibly outside, with a new cable. If it still arcs, toss it out and buy a new one. If it seems fine, activate the power supply by connecting the green wire in the ATX connector to any black wire with a paperclip (look it up for details). If it still works, you can reinstall it into your computer.
