Re: [CAD_CAM_EDM_DRO] Re: Gecko power supply transformer

turbulatordude wrote:

>If I can add to the question......
>
>I've recently ran across some references to rating for a center tap
>vs. end to end of a 3 secondary wire transformer.
>
>

There are two ways to build a full-wave power supply. First, you use
a plain single secondary winding transformer (2 sec. wires) and a bridge
rectifier. Since 2 diodes in a bridge rectifier are conducting at any time,
the voltage drop (pretty insignificant) is doubled, and the power that must
be dissipated is doubled. That is significant, as it will fry the rectifier
if you don't get the heat out. You take the RMS voltage reading of this
winding and multiply by 1.414 to get the DC voltage on the capacitor.

The other way is with a center-tapped secondary. You get the full winding
voltage divided by 2, times 1.414 as the output voltage. Since there is
only
current flowing in one half of the winding at any time, the current delivery
from the secondary is increased. So, if it has a rating of 5 A at 32 VCT,
you may be able to draw about 7A at 22 V from it. It depends on whether
the current rating has already been changed to reflect the full-wave
rectifier
condition (where you can't increase it again), or if it is a plain,
full-winding
RMS current rating (where yu can increase current by some safety margin,
but not fully double it).

Jon