+ Post New Thread
Results 1 to 5 of 5
  1. #1
    Full Member level 5
    Points: 5,732, Level: 17

    Join Date
    Oct 2005
    Posts
    253
    Helped
    40 / 40
    Points
    5,732
    Level
    17
    Blog Entries
    1

    Who sells toroid cores? I need small quantity

    Looking for power toroids.
    I have one obtained from a junked car audio amp, probably supplied 200W and
    operated at 40khz.
    So I been looking for who sells empty cores like that ?
    not digikey or mouser apparently.....
    Want small quantity, so all those google hits from china are no good.
    Thanks

    •   Alt5th September 2010, 14:38

      advertising

        
       

  2. #2
    Advanced Member level 3
    Points: 5,700, Level: 17

    Join Date
    Jul 2010
    Posts
    923
    Helped
    289 / 289
    Points
    5,700
    Level
    17

    Re: who sells toroid cores?

    This will be somewhat based on your country.

    Surplus/Scap dealers can have some. Ebay as well. Keep in mind that not all toroids are suitable for your use. Some will be made for EMI devices, some for inductors, and some for power transformers. Some EMI-targeted cores might be suitable for power transformers in some cases (though power-transformer optimized materials are still better). There are also some expensive saturable reactor cores which likely won't be what you want. This makes it very hard to find known cores, as most places just advertise them as "ferrite toroid".

    •   Alt6th September 2010, 04:45

      advertising

        
       

  3. #3
    FvM
    FvM is offline
    Super Moderator
    Points: 170,606, Level: 98
    Awards:
    1st Helpful Member

    Join Date
    Jan 2008
    Location
    Bochum, Germany
    Posts
    27,104
    Helped
    8396 / 8396
    Points
    170,606
    Level
    98

    Re: who sells toroid cores?

    not digikey or mouser apparently.....
    Digikey has a collection of epcos ferrite cores, hidden by an inappropriate product category. You have to consult the epcos datasheets to identify suitable types. Ferroxcube is another vendor with a large toroid core offer.

    You should identify the correct core material for your application. In my opinion, standard core shapes (E, EC, ETD) are often superior for power transformers.

    •   Alt6th September 2010, 07:12

      advertising

        
       

  4. #4
    Full Member level 5
    Points: 5,732, Level: 17

    Join Date
    Oct 2005
    Posts
    253
    Helped
    40 / 40
    Points
    5,732
    Level
    17
    Blog Entries
    1

    Re: Who sells toroid cores? I need small quantity

    FvM
    Thanks, so yes digikey, very good now!!

    I would think like B64290L0038X087, N87 material is good for what I want to experiment with.

    Regarding toroids in general for power conversion, so you think they are not so good ?
    they must be very good in terms of stray magnetics, as why they seem to be exclusively used in DCDC 12V/+-35V in car audio amps.

    Efficiency ?


    Re ETD,E etc, I do have some pieces ETD34,ETD29 purchased locally from Farnel,
    however I feel Farnell's prices are not so competive.
    Also why Feroxcube stuff 2-3x more expensive than Epcos>
    Farnells range in these parts isn't all that great either,
    as yet I don't know of another convenient online supplier.....


    It would be great if digikey or mouser stocked those items, but again I don't see them,
    though Mouser have some, but not complete set for a eg ETD39 or whatever, like wtf?
    selling cores but not clamps or bobbin ? weird!!

  5. #5
    FvM
    FvM is offline
    Super Moderator
    Points: 170,606, Level: 98
    Awards:
    1st Helpful Member

    Join Date
    Jan 2008
    Location
    Bochum, Germany
    Posts
    27,104
    Helped
    8396 / 8396
    Points
    170,606
    Level
    98

    Re: Who sells toroid cores? I need small quantity

    The most serious disadvantage of toroid core inductors is the windings technology. Some techniques, e.g. screens, are effectively impossible. Also you can't introduce air gaps. Thus their production share for power inductors is small now. But if they fit your application, very well.

    Retail list prices of epcos and ferroxcube should be competitive, in addition there's a lot of other vendors. But catalog distributor prices can vary by a large factor, of course.

    Basically their offer reflects the demand. They'll probably kick out parts that are only ordered once a year...

+ Post New Thread
Please login