Re: welding machine as a power supply

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.

BY my digital meter, with the capacitor doubling it makes 68vdc rock
steady...

I worried about the drives too. No problems with the drives thou. I am
using a opto solid state relay in the 220 circuit going to the
transformer. I am using that for a E-Stop, definite "WHoa" for my
machine. The geckos had a Enable circuit, the Larkens do not.

You use what works.

NO transformers on ebay, one of the hardest items to scrounge up to
build a cnc. I have 3 here, but are HEAVY out of a golf cart battery
charger

David



--- In CAD_CAM_EDM_DRO@yahoogroups.com, "ftomazz" <filipetomaz@p...>
wrote:

> Thanks to all that replyed.
>
> It is for a router, probably 4000mm x 2000mm x 300mm working area. It
> is expected to machine, among others stone, wood and aluminium. The
> motors I got (still expecting) are 3 servo motors 65V 10A max
> ratings. The power supply I would buy it from Doug Fortune, but the
> import taxes and the air mailing are very high (I am in Portugal). So
> I was looking for another alternative.
>
> Filipe
> http://mastor.no.sapo.pt