how to short out a PSU to test some parts without a motherboard?

[LOUISSSSS]

i have an old FSP Epsilon FX-600-GLN.

i'd like to use it to power on a water cooling pump that will be 12v with a 4-pin molex adapter.
and also test out some fans and small leds (12v)

what is the propper way to do it? i can't seem to get my FSP on by connecting the Green wire to any other black wire on the 24pin...

what i think is right:
1. use paper clip to connect green + any black wire on 24 pin
2. connect pump/fan/led to molex adapter on psu
3. plug in psu to wall
4. turn on I/O on back of psu
5. wait for 30-60 second lag....

i tried just that ^^ and the psu fan never came on, nor did the fan i had attached to the psu

 

[speedfreak]

have you tried other devices and see if it works? like a fan or something?

 

[Yellowbeard]

Originally posted by: LOUISSSSS
what i think is right:
1. use paper clip to connect green + any black wire on 24 pin
2. connect pump/fan/led to molex adapter on psu
3. plug in psu to wall
4. turn on I/O on back of psu
5. wait for 30-60 second lag....

i tried just that ^^ and the psu fan never came on, nor did the fan i had attached to the psu

Try connecting several devices as some PSUs want to see more of a minimum load than others. 1 fan may not be enough.

Diagram: http://www.houseofhelp.com/for...showthread.php?t=63991

 

[Modelworks]

Try connecting the black and green after you have the power on.
Some supplies will not start unless the logic cycles, off then on.

 

[LOUISSSSS]

can i use the gree + any black?

 

[LOUISSSSS]

and is doing this bad for the psu in any way?

 

[roid450]

Originally posted by: LOUISSSSS
can i use the gree + any black?

Green and any black, use a paper clip, bend it as needed and jsut stick it into the 20 or 24 pin mobo connector. I've heard that PSUs can potentially die or go bad if you don;t have enough load on them when doing this, a few fans maybe CD/DVD drives should be ok, maybe also a old HDD :thumbsup:

 

[WoodButcher]

Originally posted by: roid450

Originally posted by: LOUISSSSS
can i use the gree + any black?

Green and any black, use a paper clip, bend it as needed and jsut stick it into the 20 or 24 pin mobo connector. I've heard that PSUs can potentially die or go bad if you don;t have enough load on them when doing this, a few fans maybe CD/DVD drives should be ok, maybe also a old HDD :thumbsup:

I always use an old Hard drive. I read somewhere about the psu needing a load on the 5v rail and the HD does this. Another option would be to wire a fan to the 5v.

 

[mindless1]

These days, manufactuers have wised up and any rail which would need a load to not self-destruct will have that bare minimum load resistor inside the PSU already.

However, that is not enough to keep the PSU running if you had an *imbalanced* load on one rail of some PSU. For example if it's group regulated and that is biased on 5V voltage which is very common, a large load on 12V will droop the 12V voltage level, or vice-versa 12V might rise too high, and over/undervoltage circuits can keep PSU from seeming to turn on long enough to tell it tried to, or turn it off once running. More elaborate PSU may sometimes need a load on the 3.3V rail to keep it in spec.

Consult the manufacturer's datasheet, if it's proper it will list their official minimum loads. To keep 12V level high enough you may find you do need a small load on the 5V rail, a hard drive would work, or something quieter and smaller like a 5 ohm, 10W power resistor (which will get fairly warm to hot).