Using A Power Supply Tester

V

voyager

Geek Trainee
I've had several PS's die on me through the years.
So, I finally bought a PS tester after the last one died.
I bought a re-branded version of the CoolMax PS-228 type.
I can find little to no information on how to use this type of tester.

So, my story:
3 years into a 5 year warranty, I RMA'd a faulty PS.

The 1st refurbished replacement [refurb#1] started and seemed to be OK, at first.
Then, after shutting the PS off, the tester gave a strangled squawk while the PS shut down.
It would not restart.
I tried again the next morning.
The PS still would not start.

They sent me another refurbished PS [refurb#2].
It seemed to be OK.
The tester made no noises on shutting down, but the PS would not restart after turning it off.
I would have to wait 5 to 10 minutes before it would restart.

Then, I tried refurb#1 again.
It started up and seemed to be OK, but the tester still makes a variety of sounds when the PS is shut down and it will not restart without waiting 5 to 10 minutes, also.

Q-1.
What does it mean when the tester makes a single beep, or a strangled squawk, or a long drawn out warbling squeek after the PS is turned off? It has done all 3 and then some or none after shutting down refurb#1 .

Q-2.
An older spare PS looks OK when on the tester.
It can be turned off and restarted immediately while on the tester.

Refurb #1 and #2 can be restarted without the 5 to 10 minute wait if the tester is disconnected, then reconnected to the PS.

Anyone have an explanation for what the reason for this is?
 
Those simple PSU testers are not reliable. They are only able to tell if voltages are OK with almost no load. So even if tester says PSU is OK, it may be not. If those PSU's are bad quality, then there is no point to test them. So what are manufacturers and models of those broken PSU's?
 
I understand that the cheap PS tester has limitations. It is not a true PS tester, but only a no load voltage and PG tester.
It is little more than an easier way to do a manual voltage check.

The PS's referred to in my OP:

original failed PS = OCZ-ZT750W
refurb#1 = OCZ-ZT750W
refurb#2 = OCZ-ZT750W
Older spare PS = Antec EA380 [came pre-installed in a case purchase - was replaced with a better PS]

Q-1 restated:
When I spoke by telephone with a tech at FirePower about the problem with refurb#1, he immediately agreed to send me another unit when I told him how the unit had failed.
The fact that the tester made noises after shutting the unit off meant something to him.
I would like to know what is indicated by that occurring.

Refurb#1 had been non functional since its failure until I checked it again after refurb#2 arrived and I had checked it out.
It still causes the tester to make noises after the unit is switched off.
It now makes a variety of different noises from one shut off to another.
The tester does not make any noises what-so-ever after refurb#2 is switched off.

Q-2 restated:
The older spare PS works smoothly with the tester, no hiccups, no catches.
The refurbs or the tester seem to have some issues with trying to restart the refurb PS's immediately after the fan stops after turning the refurbs off.
The need to wait a longer period of time or to disconnect and reconnect the tester indicates to me that something needs to reset, discharge, or ?, before the PS will start up again.

I am curious as to what the reasons might be.

As long as I'm here again, let's add another question.

Q-3:
When switching the PS's on, they do not seem to start up without the tester or anything else connected to them.
The fans do not turn until they are started with the tester connected.
What is happening with this?
Would the jumper wire used in a manual voltage check be what allows the PS to start up?
 
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I've never used a power supply tester myself, but my first thought was if it has a manual. If it didn't come with it, there should be something on line. I don't know if there's a universal standard to the testers, as I imagine snagging a multimeter might be more useful.

Not sure on the first 2, but for the 3 one, you need to jump it as a circuit needs to be completed for the power supply (and system on an assemble computer) to start. You're bypassing the power switch in a sense.
 
This particular PS tester is a Chinese made product that is marketed under a number of different brand names, all of which are basically the same tester, and are sold for prices ranging from $12 to $40 from what I've seen.

I can find no user manual for this product other than a web page that says it is the manual.
I copied and pasted it into a text file which I have copied and pasted here:

Code: 
ATX Power Supply Tester MANUAL
for ATX 20-pin & 24-pin Power Supply

The product designs with LCD to show ATX power voltage. Easy to plug with ATX power 20/24 pin and plug in (P4/P6/P8) to show the voltage on the LCD panel.

Features:

The product designs with LCD to show ATX power voltage. Easy to plug with ATX power 24 pin and plug in (P4/P6/P8) to show the voltage on the LCD panel.

  Easy to check ATX power supply
  Aluminum case
  Accurate voltage indicator +/- 0.1V (+12V1/+5V/+3.3V/5VSB/+12V2/-12V)
  ATX P.G. value display
  Lower or higher P.G. values alarm
  ATX output connectors check
  Lower voltage detected alarm
  Over voltage alarm
  No voltage detected alarm

Manual:

  Plug-in your ATX power 24 pin and plug-in (P4/P6/P8) into the tester.
  Turn on your ATX power supply
  LCD shows each voltage and P.G. value on the screen automatic and you can hear 2 beep sounds.
  ATX power output connector checking one by one.
  If power output is working, the LED will light on.
  If power output failed, the LED will not light on.
  Plug-in (HDD/Floppy) connector and check LED light (+12V1/+5V)
  Plug-in SATA connector and check LED light (+12V1/+5V+3.3V)
  Remove the connector after your checking
  Do not plug-in 2 connectors into the tester at the same time
  (Not include 24 pin connector)
  Abnormal voltage detected will not display on the screen.
  No voltage detect, “LL” will display on the screen.
  When detected Voltage is lower than Min. Value, “LL” will display on the screen.
  When detected Voltage is higher than Max. Value, “HH” will display on the screen.
  When detected voltage is lower than table value (A), will alarm.
  When detected voltage is higher than table value (B), will alarm.
  P.G. value detected lower 100ms or higher 900ms, P.G. value is abnormal and alarm.
  When abnormal happened, it will alarm and relative digit blink on the screen.

Normal Voltage Range:

  ±5% for +5V, +3.3V, +5VSB
  ±10% for +12V1, +12V2, -12V

  xxx   Normal Voltage range       Display Voltage range

  xxx          xxx     Lower (A)    Higher (B)    Min. (C)    Max. (D)
  +5V       5.0V    +4.75V          +5.25V          4.0V           6.0V0
  -12V       -12V    -11V              -13V              -10V            -14V
  +12V1    12V      11V               +13V              10V             14V
  +12V2    12V      11V              +13V              10V             14V
  +3.3V     3.3V    +3.14V       +3.47V           2.0V           4.5V
  +5VSB    5V      +4.75V        +5.25V           4.0V           6.0V
  PG           xxx        xxx                xxx                0ms          990ms

The info given is very basic and nothing more.
Apparently, if one has the knowledge about PS's and their testers, more diagnostic information about the PS can be gleaned from its actions.
 
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What power supplies are you using? I mean, I've had one or two die in my day, but having a rash of them seems pretty odd and typically, low-end, garbage units go OR you have something going on with the socket or circuit the computer is on. No power supply tester is going to be able to tell you the quality of a power supply. If you have these units unable to power on a tester, that might be an indication they're bad. Using junk like what's bundled in PSU+ case deals, or crappy brands like Apevia/Aspire, Coolmax, or something really cheap is never a good idea. For example, a good 500W unit is typically going to run $80-100 USD. Excluding a killer sale on a good unit, you probably won't find one for $40. A dollar amount isn't the only thing, but going cheap on a power supply is never a good idea. I don't care how pretty it looks on the outside, if the guts are junk all you have is a pretty box. There are equipment to load test units, but they run in terms of thousands of dollars and require some knowledge to work.

The tester is a very limited device. From the manual, besides showing if the PSU powers up at all, it only determines values without load and if they're within our outside allotted variances. That's it. If the PSU isn't powering on under a load that a couple AA batteries can handle, I'd lean more toward a power supply problem.
 
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