Re: [CAD_CAM_EDM_DRO] Transformer Soft Start

tiffyted wrote:

>Can anyone in this group advise me on a suitable circuit for soft
>starting a 230v primary, 40v secondary 1000VA toriordal transformer.
>
>I have one I want to use with my Gecko 201's, but it keeps blowing
>the mains fuze on power up.
>
>
>

I think you have something serious wrong, here. I don't think soft start
will help you. it is possible the transformer is defective. Are you sure
it has a 230 V primary? Is it a split primary, 2 coils that can be
wired for either 115 or 230 V? If so, an incorrect connection in either
setting will blow fuses. The phase of the two windings must be correct
for it to work.

First, I'd disconnect the secondary wires and see if the problem still
ocurrs. If not, then most likely the rectifier is bad or wired wrong.
If it still blows, you need to check the primary wiring with the
manufacturer,
or with someone who has successfully used the same transformer on 230 V.

If you can't get any help on this, wire a 230 V light bulb in series with
the transformer primary. If the bulb glows at full brightness, the
transformer
must be appearing as a short. With the recifier/capacitor connected, it
should glow brightly for a few seconds, and then begin dimming as the
capacitor slowly charges.

Jon