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Series Connect Lab SM Power Supplies

I need a variable bench supply that will provide 0-32VDC at 30A. I already have two of these inexpensive (0-16VDC 30A) units. Please see link below for full specs:

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I have heard SMPS's can be operated in series if a diode in placed across the connected positive and negative leads to prevent one from loading the other.

Can someone please confirm this?

Also, is it necessary, or preferrable, that both supplies are adjusted to about the same voltage, ie. 10V and 10V to get 20V, as opposed to

15V and 5V, or 15V and 5V?

Is the amp rating affected at all by doing this?

Thank you for any assistance.

Lary Underwood

Reply to
Larry Underwood
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Oh, I forgot to ask ... would it be acceptable to string five 6A diodes in series, rather than use one 30A diode? I realize there will be a 3.5V drop due to this.

Thanks again,

Larry

Reply to
Larry Underwood

I don't think so. Those things probably have the negative output grounded, so connecting them in series will short the "top" one.

See the manual- output current for each output voltage- and choose the lower of the two currents if they are not equal.

Best regards, Spehro Pefhany

--
"it's the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
Reply to
Spehro Pefhany

No- diodes connected in series will have the same current rating, since all the current goes through each diode.

Best regards, Spehro Pefhany

--
"it's the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
Reply to
Spehro Pefhany 

--
The diode isn't needed.
Reply to
John Fields

5 diodes would not drop 3.5 volts. 0.35V maybe.
Reply to
MrTallyman

You are an idiot. DC power supplies have full floating outputs.

Reply to
MrTallyman

[...]

Once in the university, there was a need for a 100KV supply. There were

25KV supplies with both terminals isolated from ground. Professor connected four of these in series without any doubt in mind :))) True story, I omit the names :)

Vladimir Vassilevsky DSP and Mixed Signal Design Consultant

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Reply to
Vladimir Vassilevsky

HVDC supplies will almost certainly, always be fully isolated. Any grounded element is by customer option or deliberate action. And it will NOT always be the negative node.

Reply to
The Great Attractor

I see no documentation that says this supply has isolated outputs. I only see two terminals, and the third ground terminal is missing. With out any experimentation, I would say it cannot be used in that fashion.

Cheers

Reply to
Martin Riddle

AlwaysWrong, how *do* you do it?

Reply to
krw

He said "series."

John

Reply to
John Larkin

Reminds me of games that a tech-to-be-nameless (Hi, Mike!) played with a tray of discarded 9 V batteries. They snap together *so* well in series.

--
Rich Webb     Norfolk, VA
Reply to
Rich Webb

Maybe he is really, really smart and just pretends to be AlwaysWrong.

John

Reply to
John Larkin

I have three HV bench supplies. All have the BNC-type HV connectors, with one side grounded.

John

Reply to
John Larkin

If he was that smart, he's have a job and be so busy he wouldn't have time to go online.

--
You can't have a sense of humor, if you have no sense.
Reply to
Michael A. Terrell

I wonder what sort of performance you could get from a drag racer powered by 9 volt batteries.

John

Reply to
John Larkin

*No* one is that smart.
Reply to
krw

What diode (or five) would be only .35V at 30A?

Reply to
krw

This one maybe, if you let it warm up a bit:

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Reply to
Spehro Pefhany

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