From: Spehro Pefhany <speff@interlog.com>

The renowned peter michaux <porkproducts@home.com> wrote:

> it doesn't look like there is a capacitor in there. Can someone explain to
> me why there are both AC and DC readings?

There is no capacitor, that's why there are both AC and DC readings. Why
you get the readings you do has to do with the nature of the full-wave
rectified AC and the way voltmeters work.

Suffice it to say that you will get more like 16VDC if you put a big
capacitor on the output.

Regulation (assuming that 17V or 20V won't fry the driver) isn't all that
big a deal, a chopper driver will do it's own regulation of the current.
You should keep the ripple level to +/- a volt or less, so that means the
capacitor has to be C ~= 4000uF per ampere of current at 60Hz.

So, with the BF capacitor, and *if* the driver will take the
extra voltage, it should work ok.

Best regards,
--
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Spehro Pefhany --"it's the network..." "The Journey is the reward"
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