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Forum Index : Electronics : sources for inductor cores.

Posted: 02:05am
01 Aug 2025
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johansen
Newbie

I have a number of bosch bova inverter boards, most of mine are 3 to 5 tons and as a result they have a 5Kilowatt capable input PFC front end section and a 30 amp rated igbt block for the compressor. Some of them also have what has to be a 50 amp rated screw terminal 3 phase diode block, others use smaller circuit board mounted rectifiers.  also the heatsinks are quite large.

Basically bosch requires the hvac companies to sit on the broken inverters for something like 3 months, and after that they can toss them in the dumpster. I don't see any for sale on ebay unless they still work, which tells me they all end up in the dumpster, which is how i have about 10 of them over 2 years, from one company alone that is not particularly large, typically they have just 2 installers, an office worker and the boss who got caught with the office worker and then divorced a few years back lol..

Some of the boards are different and they have a 2 phase continuous current PFC front end, as opposed to 3 circuit board mounted toroidal inductors that are much smaller.

So anyhow I think I have 4 of these inductors, 2 for sure, the cores measure 25mm wide by 13.5mm deep with an inner diameter of 41.5mm and outer of 68.5 of which the plastic housing reduces the ID down to 37.5mm

The air gap (not adjustable) in the core of 5.4mm makes,  assuming these are amorphous met glass cores, at 1.5T field strength it would take 6400 amp turns to get there. (a glass like metal tape just a thousandth or two in thickness, but no markings as to what it is exactly)

40 turns would get you to 125uH and would saturate above 160 amps.

if anyone wants one let me know.
Edited 2025-08-01 12:07 by johansen
 


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