power supply question, can it provide 15 amps?

[Higgler]

Could someone give an opinion on this power supply,

http://www.mcmconnect.com/pdf/electronics/spec_sheet/72-7700.pdf

It's a Tenma 72-7700, If it says 24VDC and 15 amps on the spec sheet, will it provide 15 amps, or does the word "limited" hint it might make 15 amps at some lower voltage than 24VDC. I'm so confused. I bought thru Newark In One.

A coworker has done a short test and thinks it's not a 24VDC x 15 amp unit.

Thanks,
kch

 

[melone]

If it does not provide 15Amps @ 24V, then it isn't working properly. Return it.

 

[Madcow]

Looks like it should do it. You have to
make shure the current limit knobs are turned
all the way up.

 

[Higgler]

My coworker just brought me a dollar. I bet him it would work, even with the "limited" word. We needed to put the proper load on it.
For some reason, the product comes with leads that say 3 amps maximum on them? That added to the confusion, weird. It's like buying a Ferrari with 60 mph tires.

Thanks for your input Madcow and melone, you were both correct.

kch

 

[itsmoked]

I have a 1500W HP supply with "DO NOT EXCEED 3A" on the connectors. Very annoying! You have to go to the back to access lugs.

'Limited' could however mean a duty cycle! Beware.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[Higgler]

They put the 3A printing next to the "-" output of the supply, still not sure what that means.
I think limited suggests 15 amps no matter what the voltage you try.

thanks,
kch

 

[IRstuff]

I think that it's exactly as Keith's system. The front panel connectors and cables are not rated for the full current. There should higher current connections in the back.

The "limited" applies to the knobs for adjusting the current limit.

Is there an owner's manual?

TTFN

Eng-Tips Policies FAQ731-376

 

[Higgler]

IRStuff, I'll check that out, a coworker has been handling that.
I do recall plugs on the back of the unit, under a protective plexiglass bar, but I thought that was for input 60 hz, I think I'll go look.
Thanks for the tip to the tip.

Kevin

 

[itsmoked]

AH! Naw, that's where you get the 15A at.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[legalimit]

Some power supplies "fold back". They deliver say 15 amps but if more than this is drawn, say a short circuit,then they reduce the current to a much lower level.

 

[Higgler]

I did check out the back of the power supply, it does have terminals for the high current output. Hence the 3 amp cables sent with it can only be used in the front banana plugs.
We used the unit at 24VDC and 8.5 amps current draw.
Pretty nice unit for $350.

legal limit, we did put a short on the unit and it folded back the voltage while putting out 15.3 amps. On the supply title it said "24VDC, 15 amps (limited)". Maybe that is to show the reader that they put out 15 amps no matter what the voltage and reduce the voltage when more than 15 amps are needed.

kch

 

[IRstuff]

That's what that means, you can limit the output current frmo 0 to 15 amps

TTFN

Eng-Tips Policies FAQ731-376

 

[zeitghost]

Foldback current limiting would have reduced the output current under short circuit conditions to less than 15A.

This reduces the stress on the pass transistor.

From the sound of it, the psu has an ordinary current limit of 15A.