back to inlet board salvage project

rack 48v PS inlet filter board:




A 19-inch powered rack was being scrapped, and I snagged a few of the removable power supply modules fron the
bottom shelf. After CONSIDERABLE disassembly I was able to dig out the discrete inlet board. This supply is
6kw and was designed to filter 220vac, but the filter layout will work for AC or DC. This board is a bit odd
in that it's long and narrow, instead of the usual roughly square shape. But the components are pretty beefy
so it would probably work acceptably well for decent current DC filtering as well as AC. Considering the wire
on the chokes, it should have an acceptable voltage drop at 15-20 amps.

In addition to the usual capacitors and MOVs, it has two stages of common mode transformers, and even a gas-
discharge arrestor with twin 30 amp fuses. It's a pretty nice all-around filter, worth the effort to salvage.

I drew up a schematic by hand and also on lush projects, although they have a limited selection of components
and I had to improvise on the MOVs, common-mode chokes, and gas-discharge lightning arrestor. Also, I have
no indication of the choke values and the other parts aren't marked clearly, so this is just a general layout
schematic. It's not like you're going to be building one of your own, just go find one and give it a go.



lush projects drawing

lush projects drawing	pencil schematic	removed inlet boards

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