Info Power Supply Tester

[Spithre]

Power Supply Tester

I thought I would share this for those who might not have thought of getting one.
Many wonder 'Is it my power supply?' when something is going wrong.
Well, they have testers for that. I recently got one, and it works great--in telling one if a PSU is good or bad, or if a part of it is not right.

This is just one example of the many out there--this is the one I bought.
Also, since it has been a long time form when one could just turn on a PSU that is not plugged into a motherboard and it work
(rather, modern power supplies require being plugged into a motherboard before working), this tester 'tricks' the PSU into thinking
it is plugged into a motherboard, and runs the PSU all by itself, away from any motherboard.

You can test all cables, including SATA, molex, fan, 8-in, 6-pin, HDD.

These testers remove doubt about what might be the culprit in computer problems--at least hardware-wise.
(and there are also motherboard testers, too--they plug into a PCI-e, PCI or old ISA slot)

 

[RememberThe5th]

Thats actually not a way to test PSU.
Thats just an Power on Test!

You can do that only by shorting an green (PSU power on and any black wire (ground)).

The proper test is by testing its stability, but PSU varies by manufacturer or by crap PSU's that are made out there.

Even if it powers on, you are still unsure how many watts can it spit out despite on label (I would make exeption to tested PSU's, like jonnyguru's site that has reviews and also other tech hardware sites).

Lets take an example;
You need load on 12V to pull out the rated amperage (Lets say 20A), you made dummy load of 20A and check it with multimeter, you get the 20A load, now you need osciloscope to see if the mV (Voltage fluctuaction is withn the range max is around 150mV), and third is the +-5% mark of the volage shall not exceed of any voltage.

And what if the PSU blows on that 20A load? Or it cuts out power?What if cannot reach the specified value and can do less?

 

[Spithre]

The LED lights won't light if under a certain thresh-hold, indicating the PSU is bad.

 

[CountMike]

Unless tested under full load, all other test just indicate voltages present and eventually within accepted limits (usually +/- 5%) but that's on idle not under full load when tolerances should be even tighter. Another check is for voltage smoothness which only an oscilloscope can detect.
So, instruments like that can only be usefull for quick check if all parts of PSU are working but not the quality of power produced. Good to have anyway.

 

[Spithre]

These power supply testers are still useful for the average computer person, in the case of them having a computer that isn't turning on, showing no PSU fan working, and needing to find out "Is it the power supply, or what?"

Plugging the PSU into it, you find out pretty quick if the fan spins up or not, ruling out that and letting you know that the CPU (as was my case, in the last few weeks) was the culprit. At the time, I didn't know if I had bought a bad power supply (it was used, came with dust in it, which I blew out). Even the PSU I replaced that one with didn't have its fan going.

I get the 'scope readings--amps, voltages, etc.--and how a PSU can SEEM okay but not be okay, in certain circumstances. Maybe they need better testers, with all of that, too, being done automatically for the novice. More fine-grained readings. I didn't see any like that when I bought mine.