Need help converting transformer

[DarpMalone]

I'm a newbee, but thought this would have been straight forward. I'm hoping someone can help me with this.

I purchased this Cerwin Vega amp from ApexJr.
http://apexjr.com/Cerwinfullrange.htm


The amp uses 220v inputs. Since I live in North America I purchased a new 110v 600VAC transformer to swap out (I plan on running 3 of these CV boards off of the one transformer).
http://apexjr.com/Genesis.htm

The old 220v transformer 48v secondary uses 3 wire is CT (48-0-48), but the secondary on the New transformer is 0-45V + 0-45V

I attempted to connect the 45v primaries by joining the neutral wires together, and connecting them to the black neutral input of the CV board, then connecting the remaining +45V's to the +&- 45v inputs on the CV board. (This blew my fuse).

The only way I was able to get the board to power up without blowing the fuse was by joining all 45V wires from the transformer and the CV board and doing the same with all of the neutral wires from the transformer and board. I expected this to blow another fuse, but it didn't. The amp powers up and plays.





Is there a better way of connecting this transformer to this board? Am I likely destroy the board / transformer or home the way it's connected now?

Thanks for your help!

[star882]

When you tried to connect it as a center tapped transformer, you got a connection wrong and shorted it out.

[tinitus]

Originally posted by DarpMalone


I attempted to connect the 45v primaries

by joining the neutral wires together, and connecting them to the black neutral input of the CV board

then connecting the remaining +45V's to the +&- 45v inputs on the CV board. (This blew my fuse).

Sounds like you may have phased it wrong

If you call it 45 - 0 / 45 - 0, the right wire of one winding connects to left wire on other winding, and is now center tap ground
I know the phase can be measured but dont know how
Maybe induction will tell, I dont know

Otherwise you need a wire scheme from manufactor
Sometimes theres also double primary

http://www.amplimo.nl/download/970xx.pdf

But hey, if it works you may have been lucky

[tinitus]

Originally posted by DarpMalone


The only way I was able to get the board to power up without blowing the fuse was by

joining all 45V wires from the transformer and the CV board and doing the same with all of the neutral wires from the transformer and board.

I expected this to blow another fuse, but it didn't. The amp powers up and plays.

Are you sure it runs on a +/- supply and not a +/0

Old trafo connections should tell

[Andersonix]

You need to sketch a diagram of your transformer primaries and secondaries to help you see what's happening (like one of these). You have missed something fundamental if you are hooking anything from the primaries (as you say) to the input of the CV board. Can you show a picture of the transformer wiring?

[DigitalJunkie]

I think he means secondaries,not primaries.

Sounds like a phasing problem to me too.

[Andersonix]

It appears this transformer should do the job, but not hooked up the way it is with the 2 orange AC inputs and both blues and reds on transformer hooked together....

[DarpMalone]

Yes, I definitely meant that the secondaries were connected to the board, not the Primary. I've had a busy couple weeks and haven't gone back to this, but I'll do what Tosh has suggested tomorrow night.

Thanks for looking at this guys!