01-04-2022, 10:16 AM
(01-04-2022, 07:50 AM)Diabolical Artificer Wrote: "That's a serious choke! But with no-maths, are you sure it's 30H 1.5A?"
No, measured inductance is at no load but I did test it with DC trying to saturate the core, I got to 2.5A and gave up which surprised me, because as you say chokes for this sort of load are usually much bigger.
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I didn't even bother much with the gap, I used the inners out of Rizla's, bout 2 thou at a guess as gaps.
That seems wrong to me, may I ask how you ascertained there was no saturation at up to 2.5A?
Quick calculations: 30H at 1.5A represents 34J stored energy.
Assuming the core is decent transformer iron which is on the verge of saturation at 1.6 teslas, then an air gap volume of 33cc will be needed to store this sort of energy (assuming the iron stores practically none, which is justifiable).
That implies an air gap of several mm, not just a few thou', with a core cross-section of, say, 2.5" square (apologies for the mixed units!). And that's the sort of order which I've had to use in practice.
