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Registered Member #3900
Joined: Thu May 19 2011, 08:28PM
Location:
Posts: 600
Long time no post. I've been meaning to buy some large ferrite toroids for a while, and the best ones I’ve found(for my coupling transformer purposes) are these mag inc. torroids: I'll be using them as step down transformers coupled to a thick copper pipe, but they're good for anything non-hv as is, and if you epoxy coat them yourself they may be even better.
I need 10-15 of them, but the minimum quantity is 25. If anyone else wants any I can redirect them to you if you live in the us, and if you pay for my shipment to you, I can do international. They're quoting me 26 usd for shipping.
Edit: the cores being ordered are here and the minimum is 50
Registered Member #3637
Joined: Fri Jan 21 2011, 11:07PM
Location: Buffalo, NY
Posts: 1068
Ah, I figured so!
I think it may be a better idea to get slightly larger inner diameter cores.
Are almost identical to the ones you were looking for, but a bit more open.
For a quantity of 50 you would still be paying roughly the same price, if not slightly less. They're half the thickness, and a bit more than half the price!
I mean I guess the only thing that concerns me (since I'm using the cores for the same purpose) is fitting enough wire through the core. I'm going to be using 14 gauge litz wire and I fear it would not fit fully through plus the pipe.
However that was just a suggestion; I'm just thinking bigger inner diameter cores may do us both a favor. I'll keep looking around for others that are a bit bigger.
Registered Member #3900
Joined: Thu May 19 2011, 08:28PM
Location:
Posts: 600
I agree about the dimensions, It fits a bit better(I go around 3/8 copper and that leaves a ~1/4" gap). The material seems a bit lower quality to me though. My fly-back cores ran a bit hot, and the mag-inc type F has lower losses than the fair-rite 78. Lower Ui as well. I was aiming for the highest Ae possible as well. If you find anything type F of those dimensions let me know, but I'd rather have a bit of space to spare rather than a lower Ui and Ae.
In the end though, If you want to go with the others thats ok, I'll just go all out and stack 10 cores: (35.6-23)*12.7 = 160mm^2
Registered Member #3637
Joined: Fri Jan 21 2011, 11:07PM
Location: Buffalo, NY
Posts: 1068
may be a bit more reasonable material grade.
I can't quite understand the core losses section though. They're both the same grade material but for some reason the one I linked shows much LOWER Pl.
Registered Member #3900
Joined: Thu May 19 2011, 08:28PM
Location:
Posts: 600
Perfect. That's the one. Do you mean that you don’t understand why 78 higher losses than F? That just has to do with how each core is made, its the same compound, but cores aren't just a bunch of ferrite dust glued together.
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Group Buy: 0F43825TC cores
