PSU testing methods

TheTaxidermist · 01-22-2006, 03:35 PM

Are there any procedures or tools I can use to test if a power supply unit is faulty, without using it in one of my computers?

ebackhus · 01-22-2006, 03:43 PM

There are PSU testers available at stores like CompUSA and Circuit City. There is also a way to power on a PSU without having it connected to anything but I don't remember the exact instructions so I won't try and wing it here.

**Doby** · 01-22-2006, 07:55 PM

Hi,

with the psu completely removed from the computer plud into wall outlet and using a paper clip short the green and any black wirer on the 20/24 pin connector, this should turn the psu on.

Then using a volt meter touch the red probe to a yellow wirer and the black probe to any black.

Do the same with the red and orange and post the readings here for us to see.

Rick

ebackhus · 01-23-2006, 09:08 AM

Thanks for that info, Doby! I couldn't even remember when I saw the technique originally and had really wanted to try it out.

**linderman** · 01-23-2006, 01:41 PM

check this out >>> very imformative

http://www.techsupportforum.com/moth...ultimeter.html

**Doby** · 01-23-2006, 05:33 PM

Your welcome ebackhus but one other note,,,,

some psu's depending on the manufactuer will show somewhat low voltages on ths rails unless there is a load put on them, this is normal, I usually plug 2 drives into it before taking readings with a volt meter they don't have to spinup or nothing but then it somehow puts a load on the psu and the voltages increase to normal.

I have not seen this with all manufactuers just some, Thermaletake for one and there manual suggests pluging in the drives before testing

ebackhus · 01-24-2006, 11:58 AM

I have a PSU where I just want to test the fans so I'm not worried about the voltages just yet.

There are some testers that can apply a small load to the PSU but I've read mixed reviews on those. I also wouldn't want to hook up a device to a PSU that may be about to crap out and spit overvoltages.

aexdri · 01-25-2006, 09:12 PM

Yes, if it is an ATX power supply (likely unless really old), buy an Antec brand ATX power supply tester (they are 10 -20 bucks depending where you buy them) Plug it into the big connector that normally goes to the motherboard - if the green light comes on when you supply ac, it is "good".
You can't meaningfully test ATX power supplies w/o a bit of a load on both the 5v and the 12v outputs, and they won't even power up unless the motherboard (or the PSU tester) shorts the correct pins (i saying turn on, another saying power is good) If it's dead and out of warranty, you may be able to simply open it up and replace a blown fuse (they're relativly easy to find once you take the case cover off) But caution, there are some capacitors in there and you might get shocked if you are careless.

Kendall

01-22-2006, 03:35 PM	#1 (permalink)
TheTaxidermist Registered User Join Date: Jan 2006 Posts: 1 OS: Windows XP	PSU testing methods Are there any procedures or tools I can use to test if a power supply unit is faulty, without using it in one of my computers?

01-22-2006, 03:43 PM	#2 (permalink)
ebackhus Manager, Design Join Date: Apr 2005 Location: SATX Posts: 14,294 OS: WinXP Pro SP3/Windows 7 RTM My System Blog Entries: 28	There are PSU testers available at stores like CompUSA and Circuit City. There is also a way to power on a PSU without having it connected to anything but I don't remember the exact instructions so I won't try and wing it here. __________________ ----------------------------- There are no dumb questions, unless a customer is asking them. Help in the fight against cancer and other serious illnesses.

01-22-2006, 07:55 PM	#3 (permalink)
Doby Moderator Hardware Team Join Date: Jan 2006 Location: Central PA (USA) Posts: 8,094 OS: XP sp2/ Vista My System	Hi, with the psu completely removed from the computer plud into wall outlet and using a paper clip short the green and any black wirer on the 20/24 pin connector, this should turn the psu on. Then using a volt meter touch the red probe to a yellow wirer and the black probe to any black. Do the same with the red and orange and post the readings here for us to see. Rick __________________ Would you like to help TSF fight cancer and other diseases??? JOIN TEAM TSF

01-23-2006, 09:08 AM	#4 (permalink)
ebackhus Manager, Design Join Date: Apr 2005 Location: SATX Posts: 14,294 OS: WinXP Pro SP3/Windows 7 RTM My System Blog Entries: 28	Thanks for that info, Doby! I couldn't even remember when I saw the technique originally and had really wanted to try it out. __________________ ----------------------------- There are no dumb questions, unless a customer is asking them. Help in the fight against cancer and other serious illnesses.

01-23-2006, 01:41 PM	#5 (permalink)
linderman Moderator, Hardware Team Join Date: May 2005 Posts: 20,440 OS: win 2000 pro / Win XP pro My System	check this out >>> very imformative http://www.techsupportforum.com/moth...ultimeter.html __________________ I still know nothing and I respect that fact, striving to improve and, along the way, help anyone that comes from the place that I used to be! Power Supply Selection LEARN TO BACK-UP YOUR DATA FREE & EASY YouTube - Runtime Software DriveImage XML tutorial

01-23-2006, 05:33 PM	#6 (permalink)
Doby Moderator Hardware Team Join Date: Jan 2006 Location: Central PA (USA) Posts: 8,094 OS: XP sp2/ Vista My System	Your welcome ebackhus but one other note,,,, some psu's depending on the manufactuer will show somewhat low voltages on ths rails unless there is a load put on them, this is normal, I usually plug 2 drives into it before taking readings with a volt meter they don't have to spinup or nothing but then it somehow puts a load on the psu and the voltages increase to normal. I have not seen this with all manufactuers just some, Thermaletake for one and there manual suggests pluging in the drives before testing __________________ Would you like to help TSF fight cancer and other diseases??? JOIN TEAM TSF

01-24-2006, 11:58 AM	#7 (permalink)
ebackhus Manager, Design Join Date: Apr 2005 Location: SATX Posts: 14,294 OS: WinXP Pro SP3/Windows 7 RTM My System Blog Entries: 28	I have a PSU where I just want to test the fans so I'm not worried about the voltages just yet. There are some testers that can apply a small load to the PSU but I've read mixed reviews on those. I also wouldn't want to hook up a device to a PSU that may be about to crap out and spit overvoltages. __________________ ----------------------------- There are no dumb questions, unless a customer is asking them. Help in the fight against cancer and other serious illnesses.

01-25-2006, 09:12 PM	#8 (permalink)
aexdri Registered User Join Date: Jan 2006 Location: NorCal -CoCoCo Posts: 9 OS: XP Pro / 98SE My System	Yes, if it is an ATX power supply (likely unless really old), buy an Antec brand ATX power supply tester (they are 10 -20 bucks depending where you buy them) Plug it into the big connector that normally goes to the motherboard - if the green light comes on when you supply ac, it is "good". You can't meaningfully test ATX power supplies w/o a bit of a load on both the 5v and the 12v outputs, and they won't even power up unless the motherboard (or the PSU tester) shorts the correct pins (i saying turn on, another saying power is good) If it's dead and out of warranty, you may be able to simply open it up and replace a blown fuse (they're relativly easy to find once you take the case cover off) But caution, there are some capacitors in there and you might get shocked if you are careless. Kendall