-15V from a +15 supply

[Dan T]

Hi all, i've got a tripple PSU that gives out +5V, +15V,+15V

I really need one of these outputs to be -15V, is there anyway i can get
this from the supply??? Do i just wire the + to GND, and the -Ve end will
become -15V???

Thanks for help,
Dan

 

[John Fields]

On Thu, 26 Feb 2004 19:16:27 +0000 (UTC), "Dan T"
<d.twining@btinternet.com> wrote:

Hi all, i've got a tripple PSU that gives out +5V, +15V,+15V

I really need one of these outputs to be -15V, is there anyway i can get
this from the supply??? Do i just wire the + to GND, and the -Ve end will
become -15V???

---
Not unless neither end of that 15V supply is referenced to ground, or
0V, or common, or anything. That is, both the + and - outputs must be
floating.

--
John Fields

 

[John Fields]

On Thu, 26 Feb 2004 22:46:05 +0000 (UTC), "Dan T"
<d.twining@btinternet.com> wrote:

eeerr..when i tested it earlier it did seem that the -15V was just floating

---
Yeah, then, AFAIK no problem!

If you've got a lead which says +15 on it and another which says -15 on
it and you've got 15V between them and neither one of them is connected
to 0V, GND, common, or anything else, then connect +15V to whatever your
0V reference is and the other end will be 15V below that.

--
John Fields

 

[Dan T]

eeerr..when i tested it earlier it did seem that the -15V was just floating


"John Fields" <jfields@austininstruments.com> wrote in message
news:1rjs3096u8u3trk7ap75dhm1k74qspcpbu@4ax.com...

On Thu, 26 Feb 2004 19:16:27 +0000 (UTC), "Dan T"
d.twining@btinternet.com> wrote:

Hi all, i've got a tripple PSU that gives out +5V, +15V,+15V

I really need one of these outputs to be -15V, is there anyway i can get
this from the supply??? Do i just wire the + to GND, and the -Ve end will
become -15V???

---
Not unless neither end of that 15V supply is referenced to ground, or
0V, or common, or anything. That is, both the + and - outputs must be
floating.

--
John Fields

 

[Dan T]

its got +15V OP, -15V OP, +5V OP, -5V OP marked up on it

when i refrenece the -15V OP to the -5V OP they seemed to be floating for
some reason.

there isn't any other 0V refrence though.

when i get into work tomorrow i'll make a note of the model number. All i
know at the moment is its a schroff tripple PSU that i don't think is
manufactured any more.

"Dan T" <d.twining@btinternet.com> wrote in message
news:c1lsvd$ehh$1@hercules.btinternet.com...

eeerr..when i tested it earlier it did seem that the -15V was just
floating


"John Fields" <jfields@austininstruments.com> wrote in message
news:1rjs3096u8u3trk7ap75dhm1k74qspcpbu@4ax.com...
On Thu, 26 Feb 2004 19:16:27 +0000 (UTC), "Dan T"
d.twining@btinternet.com> wrote:

Hi all, i've got a tripple PSU that gives out +5V, +15V,+15V

I really need one of these outputs to be -15V, is there anyway i can
get
this from the supply??? Do i just wire the + to GND, and the -Ve end
will
become -15V???

---
Not unless neither end of that 15V supply is referenced to ground, or
0V, or common, or anything. That is, both the + and - outputs must be
floating.

--
John Fields

 

[Dan T]

Thanks for your help John, much appreciated. - sorry for emailing ur home
address, clicked on wrong reply button.

Dan

"John Fields" <jfields@austininstruments.com> wrote in message
news:ijus30hhcb83ahaltctous49di5ecdagen@4ax.com...

On Thu, 26 Feb 2004 22:46:05 +0000 (UTC), "Dan T"
d.twining@btinternet.com> wrote:

eeerr..when i tested it earlier it did seem that the -15V was just
floating

---
Yeah, then, AFAIK no problem!

If you've got a lead which says +15 on it and another which says -15 on
it and you've got 15V between them and neither one of them is connected
to 0V, GND, common, or anything else, then connect +15V to whatever your
0V reference is and the other end will be 15V below that.

--
John Fields