Question House breaker tripping when a new USB device is connected while the computer is completely turned off and then turned back on.

[Athsara]

So today i built a PC , When the computer is powered on normally without any USB connected the computer turns on and works , but when u turn the system completely off (from the psu and pull the cable out) and then connect a USB device from the rear and the turn the PSU switch on the House breaker will trip , but once u turn the switch off , turn the trip back on and then turn the PSU switch on without removing the attached USB then it will turn on normally , this doesnt happen consistently but happens from time to when a New USB is introduced while the power is cut off and the PSU is turned off and then power is given back from the PSU.



What could be the issue?

 

[MoroMoro]

Im no electrician, but that sounds like a problem with resistance.

 

[Athsara]

Im no electrician, but that sounds like a problem with resistance.

are u suggesting that it cud be an issue with the PSU?

 

[mmp09]

If I correctly understand, you just turn on the PSU switch. Not the Power ON Switch or button on the cabinet.

So the PSU when switched on from mains enters a Stand-By state, where it supplies minimum voltage and current required to run certain systems like LAN, RTC etc etc. Only after you press the PowerOn button on cabinet, then full voltage is supplied and system boots.

So try the same config without any cabinet and re-test with min parts. What are the USB devices in question? Does it happen with USB Keyboard/Mouse?

Some shorting somewhere is likely the cause and looks like it's strong enough to override the Over Current Protection deployed in ATX PSU.

 

[Ralston18]

@Athsara

Update your post to include full system hardware specs and OS information.

Include PSU: make, model, wattage, age, condition (original to build, new, refurbished, used)?

Disk drive(s): make, model, capacity, how full?

Very likely that there is some misconnection and/or a short.

Refer to the motherboard's User Guide/Manual and the Case Manual to double check all connections and wiring.

With power off and the build unplugged use a bright flashlight to carefully inspect the I/O panel - common location for shorts to occur. Inside and out. Also check all stand-offs.

You should not be and should not need to turn of the computer using the PSU's power switch. The computer should be shut down by using the Windows power shutdown menu. (Right click the window icon usually located in the lower left screen corner.)

 

[Athsara]

If I correctly understand, you just turn on the PSU switch. Not the Power ON Switch or button on the cabinet.

So the PSU when switched on from mains enters a Stand-By state, where it supplies minimum voltage and current required to run certain systems like LAN, RTC etc etc. Only after you press the PowerOn button on cabinet, then full voltage is supplied and system boots.

So try the same config without any cabinet and re-test with min parts. What are the USB devices in question? Does it happen with USB Keyboard/Mouse?

Some shorting somewhere is likely the cause and looks like it's strong enough to override the Over Current Protection deployed in ATX PSU.

Yeah its the PSU switch

so i swapped the PSU to my old CV450 from corsair and so far the issue doesnt seem to come up, it could be a faulty PSU but im looking further trying to replicate it incase its something else.

Yes it can happen with any device connected via usb in the back (i didnt test the front however)

@Athsara

Update your post to include full system hardware specs and OS information.

Include PSU: make, model, wattage, age, condition (original to build, new, refurbished, used)?

Disk drive(s): make, model, capacity, how full?

Very likely that there is some misconnection and/or a short.

Refer to the motherboard's User Guide/Manual and the Case Manual to double check all connections and wiring.

With power off and the build unplugged use a bright flashlight to carefully inspect the I/O panel - common location for shorts to occur. Inside and out. Also check all stand-offs.

You should not be and should not need to turn of the computer using the PSU's power switch. The computer should be shut down by using the Windows power shutdown menu. (Right click the window icon usually located in the lower left screen corner.)

I used the PSU switch to turn off since i was moving some componenents and i noticed it happenning, i swapped my PSU to an old one from my other system and this stopped happening on my new system , i connected the new PSU to the old system and i was able to replicate the issue on that.

 

[helper800]

Yeah its the PSU switch

so i swapped the PSU to my old CV450 from corsair and so far the issue doesnt seem to come up, it could be a faulty PSU but im looking further trying to replicate it incase its something else.

Yes it can happen with any device connected via usb in the back (i didnt test the front however)

I used the PSU switch to turn off since i was moving some componenents and i noticed it happenning, i swapped my PSU to an old one from my other system and this stopped happening on my new system , i connected the new PSU to the old system and i was able to replicate the issue on that.

Definitely a faulty PSU then. Make sure you get a quality PSU as a replacement. Anything from tier A for a computer with a graphics card or anything from tier B or above for a PC with no graphics card.