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PC power supply, Please Help

Discuss PC power supply, Please Help in the UK Electrical Forum area at ElectriciansForums.net

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Hello,

My PC Power Supply Unit came fitted with a 13A fuse in the power cable. When i just turned my pc on it blown the fuse and now its completely dead. I took the Power Supply Unit out and checked the label and it says:

Input Current 10A – 5A

I did not realise this as i thought the cable that came with the unit would just work straight out the box! My question is, do i use a 10A fuse or 5A?? and would they be safe to plug in a power strip?

Thank you!
 
power strip? like this?
roly-poly-stripper-2-(1600x1200-crop).jpg
 
Never tried as my wall socket is hard to get to so I use a power strip
We're trying to help you by process of elimination. Take the "power strip" out of the equation and see what happens. Also forget about 5A and 10A fuses, this is a red herring (and outside of the scope of ISITEE, which only recognises 3A and 13A fuses). Plug it into any other 13A wall socket!
 
Can a 5A or 10A fused be used? I don't think it's the cable getting old as this was replaced when the PSU got replaced. Could it be my surge protected power strip? Is it OK to plug a 13A plug into a power strip? When I flick the switch on the power strip, nothing else is turned on as I always turn my PC on first then my monitor

The fuse size wont cause the issue you're having, be it 5, 10 or 13Amp you'll get the same result with all of them.

Something is causing the fuse to blow, if it's blowing instantly then its pulling somewhere around 40-60Amps or more of fault current at a rough guess, so to me (and I'm by no means an expert, so take this as you will) it sounds like you have a short somewhere.
 
We're trying to help you by process of elimination. Take the "power strip" out of the equation and see what happens. Also forget about 5A and 10A fuses, this is a red herring (and outside of the scope of ISITEE, which only recognises 3A and 13A fuses). Plug it into any other 13A wall socket!

i dont have a PSU atm as its completely dead, i'll try tomorrow when i get a replacement.
 
Can a 5A or 10A fused be used? I don't think it's the cable getting old as this was replaced when the PSU got replaced. Could it be my surge protected power strip? Is it OK to plug a 13A plug into a power strip? When I flick the switch on the power strip, nothing else is turned on as I always turn my PC on first then my monitor

Use whatever you like but a 13A is fine. You seem to be getting hung up on fuse sizes.

Only 2 sizes are needed. 3 and 13.

If a 13 is popping even after changing the cord it’s time for a new one of whatever is on the end of it. PC, PSU or a banana bending machine.
 
i dont have a PSU atm as its completely dead, i'll try tomorrow when i get a replacement.

If its possible to safely power up the PSU before you put it in the computer , I would do that at the very least...If this one then pops, you know the problem is further back, possibly in the extension lead..

If its fine out of the PC, fit it back in and try again...

Expensive way to fault things though!
 
10-5A refers to the absolute maximum the PSU can consume at 120V to 230V respectively, i.e. 5A at 230V. It has nothing to do with the plug fuse size. Any of 5A, 10A, 13A fuses should be OK - the PSU has internal protection against overload - but the inrush on large PSUs can fatigue a 5A fuse after time. They are designed to be protected at 16A in Europe where protection is in the DB not in the plug fuse.

If a desktop computer PSU blows a 13A fuse it is faulty, end of. A typical desktop draws 1-2A on 230V maybe even less than 1A. Only if you have multiple super duper graphics cards all mining crypto would you need 1500W as mentioned above.
 
power strip? like this?
Power strip in Pink ..original..!

Classic causes for big bang ...a) Include Flicking that little 120/240 selector switch on older " Models"!
..b) They often die in a spectacular bang ,if cheap (large Black Label) No internal fuse !

( My Unsee is not working today)

Middle size 5A would be a DIY Home owner answer !
(under 10A stated on Euro plug)
99% chance , need a new power-supply/ case with free one !
-Unless cable has been damaged /trapped ...-Throw them both !
 
As above, most decent ATX Power supply units are protected by an internal T5A or T6.3A fuse but there are exceptions with some unbranded models!
The voltage selection switch if in the 110/120V position usually results in a loud bang followed by plumes of white acrid smoke as the smoothing capacitors rated at 200VDC are suddenly provided with 400VDC then overheat and vent.
There was also a problem with some supplied mains leads a while ago where both the outer insulation and conductor insulation cracked when flexed and also faulty molded plugs.
Buy a decent branded ATX PSU and try that.
 
If the 13A fuse is blowing, changing to a 5A or 3A will not help, they will just blow.
I am wondering whether you have installed any new cards in the pc, especially graphic cards?
If that is not the case, then you may have a siezed hard drive.
 
The PSU is dead, long live the PSU, fit another one.

Was this a new or old PSU? If a new one then it could well have been faulty from the manufacturer.
 
I'd be -very- surprised if an internal component beyond the PSU was causing a 13A fuse to fail. Even a seized drive or faulty caps on a motherboard shouldn't cause a fuse of that size to blow. If you've been picking up new PSU's one after another I'm guessing you're buying cheap ones, don't.

Change the lead, change the PSU, plug directly into a wall socket and then let us know what happens.

if that still takes the 13A fuse then I'd be inclined to check you don't have something going on with the socket, check for reverse polarity, and earthing problems, volts between neutral and earth etc.

If you are unable to do that, maybe it's best to call an electrician/PC repair guy at this point instead of throwing more money at PSU's.
 
The current available from a modern PC power supply 12V and 5V rail is well above the fairly small stall current of the motor in a modern hard drive. I suspect there was something else going on.

Maybe the old full-height Rodimes from the 70s/80s though!
 
Seagate 500gig Sata from an external hard drive case.
Installed drive into slide mount carrier.
Switched off pc, slid in drive, turned on pc.
Fuse blew on start up.
Further investigation showed drive had siezed.
Suspect it had been dropped whilst running.
 
Seagate 500gig Sata from an external hard drive case.
Installed drive into slide mount carrier.
Switched off pc, slid in drive, turned on pc.
Fuse blew on start up.
Further investigation showed drive had siezed.
Suspect it had been dropped whilst running.

Fair play, if that's what happened, but seems odd - stall current on the very low torque spindle motors is tiny.
 
Problem solved, it was a faulty power supply. Same brand as the first 1 as it was a replacement and again its was faulty, who would have thought, 2 faulty PSUs in a row! And no its not a cheap PSU its the Corsair RM650X which is a gold standard PSU. I've replaced it with another brand and it works perfectly fine, no popping sounding when i flick the switch.

Thank you everyone for your help
 
Problem solved, it was a faulty power supply. Same brand as the first 1 as it was a replacement and again its was faulty, who would have thought, 2 faulty PSUs in a row! And no its not a cheap PSU its the Corsair RM650X which is a gold standard PSU. I've replaced it with another brand and it works perfectly fine, no popping sounding when i flick the switch.

Thank you everyone for your help

Thanks for the feedback mate.
 
Glad you got it sorted. 9 times out of 10 it's the power supply at fault.

Even with named brand PSU's, cheaper versions in the range can have poor quality components such as inferior electrolytic capacitors. It does sound like a bad batch though. I prefer to use higher end Corsair and Seasonic power supplies in systems with powerful graphics cards.
 

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