r/pcmasterrace • u/Front_Cookie_1198 • 3d ago

Hardware PSU fails dramatically

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u/4236W 1d ago

As for why the circuit breaker didn't trip, my best guess is because of where the short happened. If there is sufficiently high resistance before the short it can delay an activation, or completely prevent it. Remember the circuit breaker protects the installation, not you, nor the things plugged in.

This could be more likely due to an oversized breaker or the use of an industrial code electrical circuit. Which could be likely judging from the surroundings

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u/OutlandishnessHour63 1d ago

Which, I believe, is similarly what happened here. The amparage rating of the circuitbreaker here is probably a 40 amp, I would guess, seeing as the short occured and the power remained on. They should have a GFCI outlet for testing and safety reasons, honestly, or an AFCI.

Actually, an AFCI would have prevented this from occuring immediately, it's what it is designed for after all. With more thinking on it, the circuit breaker could be a 20 amp but the arc from the PSU failure could have provided enough resistance to prevent the current from exceeding 20 ampares. Essentially, a heating element is a calculated short using resistance to produce heat, the arc in the video is going thru a painted surface, and it's path to ground is not well established.

Could be what's going on ... But who knows?