Help Required USB PSU Testing

The Rascals

The Rascals

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I have a Canon minidv camcorder and it won't power up, is it there a way of testing the USB psu, as I have about 40 minidv tapes to put onto computer.
I await the experts advice
 
The Rascals said:
I have a Canon minidv camcorder and it won't power up, is it there a way of testing the USB psu, as I have about 40 minidv tapes to put onto computer.
I await the experts advice
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I guess nobody tests USB psu
 
USB PSU's outputs are 5V and between 1A and 2.1A - so have you tried using your PSU to charge something like a phone (normally needs about 1A) or a tablet (may need up to 2.1A) to find out if it will charge the device in question?
 
Locate in your area one of these hummers.

Code: 
http://www.techtoolsupply.com/USB-3-in-1-Voltage-Current-Capacity-Meter-p/rmt-v20.htm

Or if your handy you could get some USB plugs and jacks and make up your own.

The correct resistor(s) for a DC load and a few test points for a VOM and you would be set.
 
jeallen01 said:
Should have bought one of those USB checkers when I bought the latest small battery tester from the same ad - error of omission now corrected!
PS: based on the previous experience, it should get here a bit quicker than as promised in the ad.
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Yes mine arrived within a week.
 
A follow-on from me: Does anyone have any suggestions/leads for an off-the-shelf tester for power supplies with o/p voltages >5V because it would be very handy to have one that could be used to test (including loading if possible, so not just voltage) psus with o/p voltages of around 12-20V (and thus most external "power bricks"/ "wall warts")?

The only thing I can find so far is this one on ebay which does have 12V & 19V test inputs, but I'm not sure how well that would do the job.

BTW: in the distant past I've used dedicated Power Supply Testers (from Kikusi IIRC) for testing PSUs for various IT products , and similar ones are available now - but are rather "pricey" shall we say!
.
 
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jeallen01 said:
A follow-on from me: Does anyone have any suggestions/leads for an off-the-shelf tester for power supplies with o/p voltages >5V because it would be very handy to have one that could be used to test (including loading if possible, so not just voltage) psus with o/p voltages of around 12-20V (and thus most external "power bricks"/ "wall warts")?

The only thing I can find so far isthis oneon ebay which does have 12V & 19V test inputs, but I'm not sure how well that would do the job.

BTW: in the distant past I've used dedicated Power Supply Testers (from Kikusi IIRC) for testing PSUs for various IT products , and similar ones are available now - but are rather "pricey" shall we say!
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What's wrong with a multimeter?
 
They really need to test under load, which a multimeter (the usual suspects) wont do.

Try sticking a 100 Ohm resistor across the contacts though and it might do a sterling job at normal USB voltages.

Almost all issues here with USB power delivery has been with failed connectors and the lead within about 2cms from it.
 
That's what resistors or dummy loads are for.
Half those PSU testers have a 1/4w Or 1w at best resistor. Might be fine for some SMPS but not most.

Old lamps are handy to use as a dummy load or if used in series as a current limiting device.

Most problems I see with SMPS is QRM!
Bean counters pulling the filter caps out, or really crap designs.
 
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I do have several m/ms, but would like something more flexible and easy to use, and then I later found this - taking the point about dummy loads (which I fully understand), then that with some appropriate resistors looks like it would make a useful piece of test equipment.
 
jeallen01 said:
I do have several m/ms, but would like something more flexible and easy to use, and then I later foundthis - taking the point about dummy loads (which I fully understand), then that with some appropriate resistors looks like it would make a useful piece of test equipment.
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Interesting bit of kit you found there.

Have a search on eBay for electronic loads. Some have displays and are reasonably priced too.
 
Thanks, I did a search and found some interesting stuff but most of it seems to be using fixed loads - but I'll take another look tomorrow. OTOH, my "limit" will be a "few" quid - so I suspect that the thing I found earlier, + some carefully chosend high-wattage resistors in a switched bank, will probably be the best "low cost" solution
 
A bag of resistors and your existing multimeter will be fine.
 
RustySpoons said:
Interesting bit of kit you found there.

Have a search on eBay for electronic loads. Some have displays and are reasonably priced too.
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Been there done that many years ago, but it needs both voltage and current reading mms at the same time, and it's "messy" - a "proper" electronic load displays both values (but they "cost"). That thing +,some resistors, or a large wattage variable resistor , would be far more useable
Edited: something like a 25-50W 0-10 Ohm w/w pot like some of those here would do the job - about £10-12 + a suitable box to take the "thing", the pot and the terminals
 
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jeallen01 said:
Been there done that many years ago, but it needs both voltage and current reading mms at the same time, and it's "messy" - a "proper" electronic load displays both values (but they "cost"). That thing +,some resistors, or a Variac, would be far more useable
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Yes never underestimate the variac, such a useful tool and not used much these days.

I've got 4 multimeter in my workshop, they are often used together but some annoy me as you cannot defeat the auto sleep/power off!
 
Channel Hopper said:
Never seen one work reliably below 10 Volts. Are you for real?
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I didn't mean for the secondary side. I was saying in general. It can't work on DC anyway!

They are very handy for powering bits of old kit up slowly or stuff you have repaired and don't want to blow up.
Use them quite a bit on SMPS to see how well they cope with voltage fluctuations etc.
 
If you guys reread my post #16 you will see that I quickly edited it to correct "Variac" to read "variable resistor" and then clarified that in terms of the rating thereof!:rolleyes:
 
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