How to test posibly wonky power supplies?

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I have two bench power supplies that I have been warned are a bit wonky. I have no other details on them besides that.

How would you suggest testing them?

I have an active load so I figured I'd load them up to their max and see what sort of noise is on their output, then put no load and again look at noise, and then also see how they handle sudden load transients. Also see if there is anything ugly in how they change output voltages.

Anything else?

Thanks!

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They haven't been able to refine the "wonky" term?

Ross McKenzie ValuSoft Melbourne Australia

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I'd be most worried when you have some sensitive parts connected (I mean electronics, not your sensitive parts) and turning the power supply on or off. Some power supplies lose regulation and can have larger voltage during startup and shutdown.

Also there might be some spikes when you disconnect a load, or connect it.

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I have experienced a cheap adjustable supply from China lose the ability to display correct voltage/current when powering PWM loads near rating. The output voltage measured correctly, per prior setting. Adding additional caps to the output helps. Having the display go random, is wonky. I would not make adjustments to V or I when wonky. It is best to switch to a better supply.

It all starts with a mental vision.

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Worst experience I have had with a power supply I was told was faulty.
After connecting the mains input to the input as per the label. I connected it to the power that was a reach away to switch on. Luckily when it blew up my face was far enough away to not get any of the explosion.
Advice: use a long stick (non conductive)

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Quote:
I have been warned are a bit wonky.

So... Put them in your junk box / parts bin and move on!

Somebody else learned the hard way that they are junk, most likely by frying some equipment.

It is the wise individual who is capable of learning from another's mistakes and mishaps.

They aren't reliable power supplies. You can learn that lesson for yourself the easy way or the hard way, your choice.

JC

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If you own a car and do a lot of work on it yourself use the "NEW" supplies as wheel chocks. Thats all they are good for.

I dusted off my Hitchikers guide to the Galaxy, and in the glossary was the definition of 'Wonky'

WONKY: tech term, used in programming either in .DEF or .EQU. To associate the truth with political correctness.

Example:

.def  temp   =r16
.def  freebie =r17
.def  trash  =r19

.equ    garbage   =PMFU
.equ    WONKY     =TF_Useless_Power_Supply

.cseg
begin:
     ldi  temp,WONKY
     ldi  freebie,garbage
     cp   temp,freebie     ;does WONKY = garbage
     breq result           ;YEP!!
     rjmp  begin           ;has not figured it out yet

result:
     ldi   trash,wonky     ;place wonky in storage
     clr   trash           ;make it go away

That program should clear it up ;) :lol:

I would rather attempt something great and fail, than attempt nothing and succeed - Fortune Cookie

 

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Please Read: Code-of-Conduct

Atmel Studio6.2/AS7, DipTrace, Quartus, MPLAB, RSLogix user

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I have been unable to get any nastiness out of either of them. The current sensor as well as the power light on one is not functional. But being that it's older than I am, I think I can allow it. I think the current sensor is probably a rotary switch that is old, and the light is probably a burnt out neon.