AC/DC Secondaries hookup question.

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cactus
Posts: 2
Joined: Wed May 21, 2008 9:34 am

AC/DC Secondaries hookup question.

Post by cactus »

I'm powering a unit with the JLM AC/DC 3-rail psu kit, hoping for +/-15VDC on the output.

I'm having a hard time understanding "A" "B" "C" & "D" on the secondaries, and how they should interact with the regulation pcb.
Unhooked, I'm reading 15vac between B & C, and 15vac between A & D, yet when I hook them up to the "AC" pins on the regulation pcb, I get OV.

What am I forgetting?

Thanks in advance.
Joseph

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Joe Malone
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Re: AC/DC Secondaries hookup question.

Post by Joe Malone »

cactus wrote:I'm powering a unit with the JLM AC/DC 3-rail psu kit, hoping for +/-15VDC on the output.

I'm having a hard time understanding "A" "B" "C" & "D" on the secondaries, and how they should interact with the regulation pcb.
Unhooked, I'm reading 15vac between B & C, and 15vac between A & D, yet when I hook them up to the "AC" pins on the regulation pcb, I get OV.

What am I forgetting?

Thanks in advance.
Joseph
You should really only be able to measure 15vac between A-B or C-D as they are the 2 15vac windings.

When using the World power kit with 2 x 15vac transformer and the AC/DC or Powerstation wire B&C to the 0v on the left hand side of the AC/DC etc and A goes to one AC IN and D goes to the other AC IN. If using 48v rail set jumper to Tripler. Set trim pots for +/-15v and +48v.

If you are after only +24vdc and +48vdc then use 2 x 12vac transformer and wire B&C together. Then wire A to one AC IN and D goes to the other AC IN. So nothing is wired to the 0v on the left hand side of the AC/DC etc. Place a link across the bottom right hand cap shorting out the negative rail. Negative rail parts can be left on or off the PCB as they will make no difference. Set jumper to Tripler. Set trim pots for +24v and +48v. Great for Neve and Telefunken gear.

Leaving out the jumper for Doubler or Tripler all together disables the 48v rail.
Joe :-)
JLM Audio
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cactus
Posts: 2
Joined: Wed May 21, 2008 9:34 am

Re: AC/DC Secondaries hookup question.

Post by cactus »

That did it!

That's amazing customer support!

Thanks,
JM

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