Re: [CAD_CAM_EDM_DRO] What have I got ?

turbulatordude wrote:

>I was lucky ?? enought to pick up a very heavy power supply from a
>print shop.
>
>The unit has three items that look like transformers.
>
>two have a center sections 4.25" x 2.25" x 4" so you can imagine the
>overall size. The third is a smaller unit.
>
>here is where it gets funny. one big and the smaller of these
>puppies only has 2 wires.
>
>I think that the unit was to power a lamp for exposing film.
>
>would I be correct in assuming that what I have are a couple rather
>large inductors ?
>

With only 2 wires, that is almost a certainty.

>Luckily, the third unit is a transformer. I need to do some testing
>to see what ratios it has.
>
>IF the large unit is an inductor(choke?) does it have any value in a
>power supply ? or anything else for that matter ?
>
>

Yes, it might. Capacitor-input filters have good 'regulation', ie. the
output voltage
stays pretty constant with reasonable current change, but they are real
hard on the
rectifiers, pulling sharp bursts of high current at the line voltage
peaks. This gives
them a rotten power factor.

Inductor-input filters have worse regulation, but they tend to draw
nearly constant
current from the line, giving them a somewhat better power factor. A
combination
of just the right inductor and capacitor can draw an excellent power
factor from the
line, allowing you to get the most watts form a particular size wire and
breaker
amperage.

But, in general, you just don't want to fool with things at this level
of complexity, until
the power levels get into the several KW range, at least. People who
want to charge
electric cars from the wall socket, for instance, get involved in this
sort of thing.

Jon