Re: welding machine as a power supply

go to www.cisco.com and look up the 7513 router, and it's I think
1800 watt ps... it's got 12vdc for DAYS and you usually pay more for
shipping than you do for the PS on ebay
jeffe

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Roy J. Tellason"
<rtellason@b...> wrote:

> On Monday 22 March 2004 12:37 am, Jon Elson wrote:
> > ibewgypsie wrote:
> > >Probably, the best thing would be 3 smaller individual

transformers. I

> > >got one large 2kva 220/24+24=48(dual tap) transformer and it

weighs

> > >about 50 pounds. It cost about $200 Local. Problems with one

large

> > >transformer is the bridge, you want to use a 35amp 600 volt cube

for

> > >simplicity. I have lost 3 of them in a year. When the capacitors

are

> > >discharged and you hit the go relay and throws power to the

drives,

> > >charges the capcitors (looks like a short for a second) it fries

the

> > >cube one time outa a hundred. I tried dual switches that would

charge

> > >the capacitor bank half wave but quickly tired of it.
> >
> > You can connect a couple Ohm resistor between the bridge and the
> > capacitors. Have a time-delay relay short the resistor after one

second.

> > This will reduce the power-on surge by a factor of 100 or so.
>
> Yeah, but since power dissipation in the resistor is current-

squared times

> the resistance, putting it on the primary side is probably a

*much* better

> idea...