Need help finding information on a Transformer.

Discussion in 'Electronics Resources' started by k_couture2000, Feb 5, 2018.

  1. k_couture2000

    Thread Starter Member

    Oct 6, 2007
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    I'm trying to replace a toroid transformer that has a faulty primary winding. It's rated for 120v line voltage with duel secondary windings that output 21vac rated to 16 amps. I've searched sites like mouser and found no suitable replacements, I also cannot seem to find any datasheets on this part even on the manufacturer's website. I have attached an image of the label on the Transformer if anyone can offer any help I would be grateful.
     
  2. ericgibbs

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    Jan 29, 2010
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  3. KeepItSimpleStupid

    AAC Fanatic!

    Mar 4, 2014
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    In the 1980's these https://toroid.com/ guys did a custom transformer for audio for me. QTY=1.
     
  4. k_couture2000

    Thread Starter Member

    Oct 6, 2007
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    The Transformer does indeed have to secondary windings. And I can only assume that they are the same voltage rating due to the label. 1 winding has two blue colored wires and the other has two yellow colored wires. The primary winding as your standard black and white wires.
     
  5. ericgibbs

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  6. MaxHeadRoom

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    Jul 18, 2013
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    There is a guy who makes Toroids to spec, it is Antech and he usually posts on ebay as Jonango.
    Also if you can find a close match, it is very simple to modify your secondary as needed by a couple of overwinds or remove winding's, I have done several this way in the past.
    http://www.antekinc.com/transformers/
    Max.
     
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  7. k_couture2000

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    Oct 6, 2007
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  8. k_couture2000

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    Oct 6, 2007
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    How bad is the pricing?
     
  9. MaxHeadRoom

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    It is quite a while since I picked one up from him, send a request for a quote.
    Also there is quite a number of Toroids on ebay right now, As I mentioned it is quite simple to add your own winding, however for dual windings it is advisable to wind together , i.e. bi-filar.
    You would need a 350va (probabally what the 336 is in the part No)!
    Max.
     
  10. k_couture2000

    Thread Starter Member

    Oct 6, 2007
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    I'm not sure what the 336 number is
     
  11. k_couture2000

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    Oct 6, 2007
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    Was able to get some information frm the company that makes the Transformer. The don't make it anymore and haven't for about 10yrs. NOW I need to find a replacement. Any ideas? I've attached the datasheet I was provided
     
  12. MaxHeadRoom

    Expert

    Jul 18, 2013
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    That model shows it has a thermal sensor in the primary, if the Pri. shows open, it is most likely this.
    Inspect the outside and see if you can detect anything, but unfortunately the pri. is wound on first so it may be hard to detect.
    It is a stupid idea anyway IMO.
    Have you tried the other sources?
    Max.
     
  13. k_couture2000

    Thread Starter Member

    Oct 6, 2007
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    I've been trying to find an equivalent replacement but it's proving difficult. I may be reading the datasheet wrong but it's not easy finding secondaries rated to 16amps each. And most other transformers of this type seem to also have duel primaries as well.
     
  14. ericgibbs

    Moderator

    Jan 29, 2010
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    hi k,
    I have spent ages looking for suitable transformer with no success.
    What equipment is the transformer used on.?
    E
     
  15. k_couture2000

    Thread Starter Member

    Oct 6, 2007
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    An os7801 imedic 500 message chair
     
  16. ericgibbs

    Moderator

    Jan 29, 2010
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    hi,
    That fits with what I found in that earlier link.
    E
     
  17. ericgibbs

    Moderator

    Jan 29, 2010
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    You could consider using two transformers, ie: each with a single 21V 16A secondary.?
    E
     
  18. Alec_t

    Expert

    Sep 17, 2013
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    Do you have space to take two smaller transformers? Might be easier to source (haven't checked what's out there).

    Edit: Eric beat me to it!
     
  19. k_couture2000

    Thread Starter Member

    Oct 6, 2007
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    Not sure, they would have to find into an area that is only ~4in in diameter
     
  20. k_couture2000

    Thread Starter Member

    Oct 6, 2007
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    That link is broken. I get an error message when I try linking to the source page
     
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