Re: current rating of transformers

The current rating of transformers realy has to do with how hot the
windings get if they heat to over about 100C the varnish on the wire
breaks down "depending on the varnish rating" then the windings short
and let out the smoke. If you can keep the windings cool you can draw
more current but this is not esey the paper or tape used to electely
insulate the windings alsow holdes the heat in. The different ways
you hookup the transformer draw diefferent current through all or
some of the winding for diefferent parts of the sign wave the diodes
in your rectifier "half or ful wave" only conduct when the secoundary
voltage is higher than the voltage in the filter cap this could be
lots of amps for 1 to 4 mila secounds out of every 16 mila secounds
or a few amps for 6 or 7 mila secounds out of 8 mila secounds
depending on how it is used.

Don

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "turbulatordude"
<davemucha@j...> wrote:

>
> Hi,
>
> If I have a 24 volt, (12V-0-12) center tap transformer like the

MPJA

> unit.
> http://www.mpja.com/productview.asp?product=7846+TR
>
> And isolate the center tap I get 24 volts.
>
> But when rectified, doesn't the current change also ?
>
> There is a note in the catalogue that for this wiring the amps are
> 1.8x
>
> The catalogue refers to required ouput amps
>
>
> full wave bridge cap input filter 1.8x to required output amps
> full wave choke input filter = required output amps
> full wave, center tap, cap = 1.2x roa
> full wave, center tap, choke = 0.7x roa
>
>
> Can someone shed some light on this for me ?
>
> Thanks,
>
> Dave