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View Full Version : inducter toroids, why is there 4 mounting holes pr toroid?


panduro
10-Aug-10, 09:46
Hi all, back from vacation and trying to get some amp time:D (AMP7 that is)

in need of help again!


the toroids are wounded, just need to get the plastic of now, but again this project gets me confused, there are 2 mounting holes per side per toroid, meaning 4 mounting holes pr toroid! am i suppose to split the litz core in 2 and use both holes in both sides or what should i do?

best regards

panduro
V-bro
10-Aug-10, 10:30
Hi, this is to be able to mount double parallel windings....

I had the red Truepath gauge litz wire with my AMP7 kits and it was twice the length needed to go round the core...

So what I did is first firmly twist the wire (for instance with one end in a battery dril and gently turn and twist it until it's a firm wire) Then I wind one litz wire all the way round the core and super glue it so it is sitting there rock solid. Then I wound the second one on top with exactly the same winding count. The super glueing helps a lot to be able to wind the second winding right in between without losing winding count.

Then you end up with four wire ends which will fit in the holes quite nicely!
panduro
10-Aug-10, 13:04
Hi v-bro,

thanks for the repply

Ok so i have to use both holes.

as i need 24 windings, i need to do two times 12.

best regards

panduro
V-bro
10-Aug-10, 19:04
No, you need two times 24...it's parallel, not in series you see...
panduro
13-Aug-10, 22:31
Hmm thats bad as its not gonna happen, the litz wire that came with my amp7 is only long enough for 30 turns.

still confused:(

panduro
V-bro
13-Aug-10, 22:59
Well, then just go for a single winding, Truepath uses this diameter too and is about just as powerfull... I wouldn't worry about it unless you're gonna go wild on this amp...
panduro
13-Aug-10, 23:09
ok, iŽll do that.

have a nice weekend

panduro
V-bro
14-Jan-11, 23:38
The latest kits have litz wire in double thickness, so you'll either have to split up the bundle or if it fits put it in one hole....
JorgeO
08-Feb-11, 02:26
V-bro
One suggestion - take the double length Litz. twist it as you've done, bend it in 2 equal pieces, twist again, cut the bend so you will have 4 wires. solder them.
This way, both windings will have the same resistance and will share current equally.

Take care,
V-bro
08-Feb-11, 10:59
The kits don't come with double lengh thin litz any more, now you will get double thickness single length...

And still what you suggest isn't practical as the length you cut before hand needs to be cut again after fitting, because you will need to pull the toroid snug to the board....

And then the resulting length difference will maybe be a two or three millimeter max. As long as you keep the winding count equal the difference in resistance will be negligible....