Bench PS: stacking DC supplies

[ErikdeBest]

So I got this transformer with 5 individual secondary windings: 120V, 120V, 105V, 105V and 1x 400V, all rated for 350mA

I want to make a bench power supply from it, feeding the primary from either a Variac or straight from the net. As there are individual windings I was thinking of rectifying and filtering them individually, obtaining 5 raw DC voltages that can be used individually, combined, or stacked for some serious high voltage.

For the 120V and the 105V windings I will use some 100uF/250VDC rated electrolytics, while for the 400V I would be using two 220uF/400V in series (with bleeders across them).

My question regards the feasibility of stacking the individual supplies: given the different voltages, can this become a problem? Morgan Jones (p354) shows how to stack two supplies, but in his case the voltages are similar.

Actually I do not think it will be a problem, but overconfidence is not always a good thing

Thanks! Erik

[SY]

No problem at all, at least when I've done it. Think of it this way- is it any different than using a negative rail of, say, -15V to power the CCS of a diff amp?

[ErikdeBest]

Hi Stuart

Thanks for the reply and the analogy, it makes sense!

Erik