Transformer wiring Question help

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yalesmith
Posts: 218
Joined: Wed Aug 18, 2010 5:55 pm
Location: Orange County NY

Transformer wiring Question help

Post by yalesmith »

Guys I have a quick wiring questions for you….I only ask because it seems that every time I wire up a power transformers I always make a mistake, lucky for me nothing ever blew up (Black face fender showman, Express and rocket clones). I am building a 5e3, better known as fender tweed. I bought the following Transformers-hammond 290ax:

http://www.hammondmfg.com/pdf/EDB290AEX.pdf

And my build is based on the Ceratone layout located here.

http://www.ceriatone.com/images/layoutP ... iatone.jpg

My big issue is that it appears that the Hammond 290AX transformer does not have a center tap and not sure where the "N" on the ac plug goes? But a discussion on where all the wires on the transformers go will also be appreciatived- 2x is always good.

Also I bought the following Carlin switch…is there a positive or negative terminal, can’t figure it out .

http://www.mouser.com/ProductDetail/Car ... 6ryg%3d%3d

Thanks for the help!
John_P_WI
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Joined: Wed Aug 15, 2007 4:29 pm
Location: Wisconsin

Re: Transformer wiring Question help

Post by John_P_WI »

Are you planning on using this Xformer here in the US?? The data sheet is for a primary 240 vac Xformer for export use....

Here is the domestic US:

http://www.hammondmfg.com/pdf/EDB290AX.pdf

Put your switch between the fuse and one of the black primary wires.
yalesmith
Posts: 218
Joined: Wed Aug 18, 2010 5:55 pm
Location: Orange County NY

Re: Transformer wiring Question help

Post by yalesmith »

Yes! US sorry about that
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Phil_S
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Location: Baltimore, MD

Re: Transformer wiring Question help

Post by Phil_S »

I think you have the wrong kind of switch. I would want a simple on-off, not on-none-off. You have a three position switch.

Get a simple DPST switch. The line feed (hot or +) goes first to the fuse, and then to the switch. The other terminal on the switch goes to one of the PT primary wires (black). The neutral (N) side of the feed can go directly to the other black PT primary wire. The ground wire (typically green in the US) goes directly to a bolt through the chassis. Give the ground an amount of slack so that in case of a serious pull out, the ground is the last to break loose.
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ToneMerc
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Location: East Coast

Re: Transformer wiring Question help

Post by ToneMerc »

yalesmith wrote: My big issue is that it appears that the Hammond 290AX transformer does not have a center tap
The secondary CT is the red/yel lead.

TM
yalesmith
Posts: 218
Joined: Wed Aug 18, 2010 5:55 pm
Location: Orange County NY

Re: Transformer wiring Question help

Post by yalesmith »

I wired it up and everything seems ok except for a horrible hum....I think it has to do with the power transformer hookup.....It seems as if the Hammond 290ax does not have a ground. right now i have the secondary CT (red & yellow wires) to ground...my suspicion this is incorrect. any ideas?

Thanks!
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ToneMerc
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Location: East Coast

Re: Transformer wiring Question help

Post by ToneMerc »

yalesmith wrote:right now i have the secondary CT (red & yellow wires) to ground...my suspicion this is incorrect.

Thanks!
R/Y CT to ground, is correct.
yalesmith
Posts: 218
Joined: Wed Aug 18, 2010 5:55 pm
Location: Orange County NY

Re: Transformer wiring Question help

Post by yalesmith »

I also initial put one of the filter caps in backward, not sure if that somehow damage the cap
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