Re: [CAD_CAM_EDM_DRO] current rating of transformers

Andy Wander wrote:

>Jon:
>
>I could be wrong, but I think you're confusing transformer output with
>stepper input here...:)
>
>If I am correct, the current rating in a transformer has mostly to do with
>the gauge wire used, and if half the winding can take 10A, so can the full
>winding.
>
>

No, it is a bit more complex. If you use the 2-diode full-wave scheme
with the
center tap, each half of the winding draws current only every other
half-cycle,
thereby giving it a "rest" or reducing the duty cycle. Of course, you also
get half the voltage that way, compared to a full-wave bridge using the full
winding. That also explains why the transformers have VA ratings. If you
reduce the output voltage, you can get more current to equal the same V*A.

Also, the capacitor input filter draws current in pulses, which reduces
the rating
of the transformer further.

>
>

Jon