Testing PSU With Multimeter

[gamer128]

So I have an Antec Earthwatts 650 Watt PSU and I need to test it for proper function through the use of a multimeter I purchased yesterday. Does anyone know a "proper" way of doing this? Someone said to do it like this:

Set the meter to 20 VDC and black lead connected to the chassis. With the computer off but connected to AC, touch the red probe to the purple wire inside the nylon connector that connects the PSU to the motherboard. > (Basically without unplugging anything somehow push the red probe of the multimeter into the back of the 24 pin connector touches the exposed wire inside of it.)

Repeat the same measurements for the green and gray wires both before and by observing behavior when the power switch is pressed

Lastly, measure any one red, orange, and yellow wires while the power system is loaded.

Now personally I don't think there is a way to do this without unplugging the 24 pin connector and others. Does know if this is a good way of testing it or not? My PSU was buzzing every now and then and I am going to test it myself as it is a rather long story honestly. Link to the whole story here if you want to read the full thing: http://www.mmo-champion.com/threads/1103511-Electrical-Issue-or-Bad-Luck?p=16185573#post16185573

Thanks!

 

[scottiemedic]

I recently did this with a Silverstone. Basically, you leave it plugged in, and short/jumper pins 16/17 on the main 24 pin connector. Then you ground black on the multimeter to one of the grounds, and test the others with the red (knowing what V they are supposed to display).

Here's a link to the thread I started and the great responses I got:

http://www.tomshardware.com/forum/329310-28-testing

And the Wiki link I used:

http://en.wikipedia.org/wiki/Power_supply_unit_(computer)#Wiring_diagrams

Good luck.

 

[gamer128]

I recently did this with a Silverstone. Basically, you leave it plugged in, and short/jumper pins 16/17 on the main 24 pin connector. Then you ground black on the multimeter to one of the grounds, and test the others with the red (knowing what V they are supposed to display).

Here's a link to the thread I started and the great responses I got:

http://www.tomshardware.com/forum/329310-28-testing

And the Wiki link I used:

http://en.wikipedia.org/wiki/Power_supply_unit_(computer)#Wiring_diagrams

Good luck.

Thanks! A few questions though. If I leave everything plugged up but with the PC off of course, wouldn't shorting those two pins just be the same as turning the system on? Even then, the only way I know how to short them is if I take a paper clip and stick it in the two slots. Again though, that would mean unplugging it from the motherboard. How would I short it without doing that? Then after I do that I just squeeze the two probes of the multimeter into the respective slots and pins like you said above? Sorry, I have never worked with power/shorting things. I'm trying to learn though. Thanks for your help! I really appreciate it.

 

[scottiemedic]

Thanks! A few questions though. If I leave everything plugged up but with the PC off of course, wouldn't shorting those two pins just be the same as turning the system on?

You have to take the PSU put and unhook all the cables.

Even then, the only way I know how to short them is if I take a paper clip and stick it in the two slots.

Yup, I used plain ole braided electrical wire (you have to keep the jumper in to maintain power).

Then after I do that I just squeeze the two probes of the multimeter into the respective slots and pins like you said above?

Yup!!

 

[gamer128]

Ok thanks! I'll do just that! Thanks for your help. I think I am good to go now. If the voltages and everything are good to go then my PSU is working properly correct? Could it still have an issue?

 

[scottiemedic]

Technically, yes, I suppose the amperage may be whacked or a failing capacitor, yada yada, everything that can go wrong with electricity (which I am no means an expert)!!

If it tests fine and not all over the place volt wise, it should be ok to run.

 

[terryd75]

For less than $20.00. you can get a PSU tester.