PSU switches off during connection attempts
PSU switches off during connection attempts
Last month I purchased a Corsair RM1000X Shift (ATX 3.0) with sleeved cables. While connecting the power supply to the outlet it tripped immediately, thinking the setup was faulty. I returned it and opted for a RM850X Shift (ATX 3.0). After using the latter for over a month with the original cables, I decided to replace them. I managed the cables using some combs and installed them for a day without any problems. Later, I attempted to improve the setup by straightening the pins more carefully and securing the cables better. When I switched the PSU off again, it tripped the breaker once more—just like before. I suspect the issue might be related to cable bending or improper installation, especially since I clamped the cables tighter than usual after 3D printing the combs. There’s no visible damage, and the breaker hasn’t tripped recently, though it was off when I plugged it in. The power source is 120V 15A, and I haven’t used anything significantly high at that voltage. Overall, it seems to be functioning normally now, but I remain cautious and curious about potential causes.
Other devices can also connect to that same circuit. A 850 watt power supply by itself shouldn't cause the breaker to trip (unless a GFCI or AFCI is improperly wired or functioning). A minor issue on the low-voltage side shouldn't trigger the breaker either.
If the power supply is turned off using the on/off button in the back , then plugging the AC cable in the connector shouldn't do anything because the on/off switch disconnects everything from the connector. If the computer is off by the on/off switch in the back is still in the on position, then when you plug the cable in the power supply some components inside the power supply will start to charge up with energy and will draw some power. There's a couple high voltage capacitors which are charged fast, and that will cause a spike of current, up to 30-40A of current, but for a few milliseconds. The fuse in your electrical panel should be the right kind rated for 15A or more, so that the fuse won't trip when you have that 30-40A spike for a few milliseconds. I don't want to go as far as calling them "slow blow" or "time delay" fuse, because standard electrical panel fuses should be designed to tolerate more than 15A current for very short periods, but if you have to I suppose you could use slow blow fuses in your panel. When you plug the AC cable in the power supply, you also have a somewhat imperfect contact until the cable is fully plugged in, so you could have for microseconds at a time spikes of current and sparks in the connector. To reduce these sparks and damage to the metals, it's always best to turn off the power supply from the switch before inserting the cable in connector. A power supply provides 5v stand-by 24/7 for as long as the on/off switch in the back is in the on position. So if the on/off switch is on the on position and you plug cable in, the 5v stand-by portion of the psu will automatically start to draw power and give 5v stand-by to the computer even when it's turned off. A short circuit in the cables going to components won't cause a problem on the mains, on the high voltage side. A controller chip in the power supply detects such issues and sends a signal to the primary side of the power supply and the power supply shuts down.
Several components were present, but they were mostly inactive except for the lights. The main items included a TV, two monitors, four speakers, game consoles, and around a dozen LED bulbs. It would have been unusual if these were malfunctioning since I’d left everything on before. I always switch the power supply off before connecting the AC cord and turn it back on afterward. Your comment about poor contact seems likely, especially since I connected slowly. Regarding your question about the power switch, it’s possible you meant that even when the computer was off, the back switch stayed in the on position. In my setup, I turned off the power supply using the back switch and then switched it back on.
I've experienced the same issue after updating drivers, with a brake tripping on the PSU two or three times. When I let my PC sit idle for about 30 minutes, it resolves the problem. My PSU model is likely the Corsair CX 750, which might help in future cases.