Fuses blowing

Hi
In the past 14 days i have had to replace the fuses in my pc power supply 9 times. Not understanding why they keep blowing, any suggestion welcome

I have tried a different lead, changed the plug and tried different sockets.
I was wondering if my PSU has gone. Its a 650watts, but not a fancy make, cost £60 and is 6months old .
Thanks
A
19 answers Last reply
More about fuses blowing
  1. Make and model?
  2. At work at moment will post full spec tonight
  3. the fuse shouldnt blow, there must be a problem with it


    amps = voltage * watts

    230v * 550 = 2.39 - in other words only 2.4amps of current going through that cable, shouldnt be suffient to blow the fuse

    in other words even a 3amp fuse should be enough

    its either the psu or your house wiring

    id suggest calling in an electrician to have a look if a replacement psu dosnt work (should be able to get a new one, its most likely faulty)
  4. I would suggest replacing the PSU before you burn your house down... THAT might be more expensive.
  5. If you have a fuse at all get a new PSU. Quality psu's don't use fuses.
  6. Minor correction "amps = voltage * watts" should read Amps = Watts / Voltage
    650 Watts / 230 Volts = 2.8 Amps. and fuse would probably be a 5 Amp slow blow.

    1) First if you are replacing the fuse with a Fast blow, the Inrush current could be causing it to Blow. Inrush current can be 2x to 4x the normal operating current - reason for slow blow fuses vs fast blow fuses.

    Little info on fuses - it is not just the current that blows a fuse, there is a time factor also. ie a 5 amp fuse will not blow if say the current is say 6 amps ( may even be 10 amps unless the time is greater than x (ie 30 mSec, don't know time as it's been a real long time since I ran some set on fuses). But exceeding the current rating, while not blowing the fuse weakens it so that say on the 10th time it will blow instantly.

    BUT: I would replace the PSU as you have a good chance of Having to replace the WHOLE computer. The first time it blew indicated a problem with the PSU. I dought that the PSU is being overloaded by system. Not enough info on system but I dought your system is over 450 W. And if sytem is operating normally the fault (cause of 1st fuse blowing) was in the PSU itself. A good PSU will simply shut down if it senses an over current on one of its output voltage rails.
  7. sir if your psu goes wrong just replace it. you should not be tinkering with the DC power going to your sensitive pc components and possibly frying them.
  8. totalknowledge said:
    If you have a fuse at all get a new PSU. Quality psu's don't use fuses.

    ^+1 100% true!
  9. davcon said:
    ^+1 100% true!

    thanks all
    ps this is my set up

    - AMD Phenom II X2 Dual Core 555 3.20GHz Black Edition (Socket AM3) - Retail

    - Corsair Hydro H60 CPU Cooler with free Akasa Apache Fan (Socket LGA1366 1155 1156 775 AM2 AM3)

    - Corsair Hydro H60 High Performance Liquid CPU Cooler (Socket LGA1366/1155/1156/775/AM2/AM3)

    - Akasa 120mm Apache Fan

    - Gigabyte GA-MA78LMT-US2H 760G (Socket AM3) DDR3 Motherboard

    - Corsair XMS3 4GB (2x2GB) DDR3 PC3-12800C9 1600MHz Dual Channel Kit (CMX4GX3M2A16

    PSU WIN Power+Plus ape750AE AS/A6
  10. Yeah your psu is an old HEC(Compucase) mid 2000's design.
    I'll assume it also has a red voltage switch = old feature no longer used in a modern active PFC design.
    You could RMA it since it must have some kind of warranty.
    Do you have a gpu in your rig?
    Personally i think you're better off going with a modern psu from Antec,Corsair,XFX,OZC,etc.
  11. davcon said:
    Yeah your psu is an old HEC(Compucase) mid 2000's design.
    I'll assume it also has a red voltage switch = old feature no longer used in a modern active PFC design.
    You could RMA it since it must have some kind of warranty.
    Do you have a gpu in your rig?
    Personally i think you're better off going with a modern psu from Antec,Corsair,XFX,OZC,etc.



    Hi
    Graphic - ATI 5670

    will order new psu Friday
    Thank you
    Andy
  12. out of interest how high a wattage do i need with my pc set up, please
    Ie is 500watts enough
    Budget max £45
  13. Great will order the
    suggested as can afford that now

    order the http://www.overclockers.co.uk/showproduct.php?prodid=CA-238-CM
  14. Hi, when you did your PC build did you use the MB stand-off on your PC case?
    It keeps the back MB circuits from shorting out on your PC case.
    I had a client bring in his PC for help and had the same problems, his MB was shorting out on the case.


    xhia said:
    thanks all
    ps this is my set up

    - AMD Phenom II X2 Dual Core 555 3.20GHz Black Edition (Socket AM3) - Retail

    - Corsair Hydro H60 CPU Cooler with free Akasa Apache Fan (Socket LGA1366 1155 1156 775 AM2 AM3)

    - Corsair Hydro H60 High Performance Liquid CPU Cooler (Socket LGA1366/1155/1156/775/AM2/AM3)

    - Akasa 120mm Apache Fan

    - Gigabyte GA-MA78LMT-US2H 760G (Socket AM3) DDR3 Motherboard

    - Corsair XMS3 4GB (2x2GB) DDR3 PC3-12800C9 1600MHz Dual Channel Kit (CMX4GX3M2A16

    PSU WIN Power+Plus ape750AE AS/A6
  15. GozerHozer said:
    Hi, when you did your PC build did you use the MB stand-off on your PC case?
    It keeps the back MB circuits from shorting out on your PC case.
    I had a client bring in his PC for help and had the same problems, his MB was shorting out on the case.


    hi the PSU is attached to the case.
    when i did this build i bought a new case, but couldn't get a power supplied to fit for some reason, so returned the case and used my old one

    I haven't ordered the PSU yet, debating weather to get a larger wattage than 450, as i have the pc overclocked, currently running at 4.2 on dual core.
  16. totalknowledge said:
    If you have a fuse at all get a new PSU. Quality psu's don't use fuses.


    davcon said:
    ^+1 100% true!

    i guess he means the fuse in the plug. in the uk everything that plugs into the walls 3pin socket should contain a fuse in the plug. i think its the law in the uk. every electrical item that plugs into the wall socket, has to be fused.
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