orac power supply

[Bert]

Hi to all
A couple of years ago I had good help from this forum in getting an orac up and running

I decided it would be nice to have the machine sitting lower on the bench so I striped out the base unit and cut of the lower section.

Oh boy what have I done,

I got carried away with the side cutters late one night

I have got the 63 volt suply for geckodrives

I need a 12 and 24 suply for auto turret

On previous instalation I had geckos mounted on circuit boards that slid into origional rack.and used a regulator fitted on to the each circuit board to lower a 24v supply on the rack to 5volts for the gecko comm terminal this worked well but as I striped out every thing I now need to put the other smaller transformer back into play to get back the 12 and 24 v

I have powered up the smaller transformer and reconected it to the origional board with the diodes and capaciters and had a check out with the meter and found what wires I need for the 12- 24v.

The bit I can't get my head round is how does the gecko get its return wire if it needs own at all

[Bert]

Ok so i have had a look around at what others have done.

I am going to do away with regulators and get or make a +5v supply that will go to the BOB and give each gecko a new supply from the +5v that will go into BOB

The only thing I have not found out yet is what amp rating does the BOB and Geckodrive need for the +5v

Found referance to using a +5 supply from pc tower but some say it is a bad idea to use pc for it

any help would be nice
cheers bert

[Denford Admin]

This might help:
http://compreviews.about.com/od/cases/a/PSUWattage.htm

I can't see why a PC PSU wouldn't work ok - it's worth trying for such little money (2nd hand)

[Bert]

I thought I read someware that a pc power supply would need to be modified if using it as a standalone supply

I have got a 12v 3amp power supply unit off a disused external hard drive that i might use as both stepper boards and the bob have been fitted with 5volt regulators or,

I could modify the power supply and reduce the output and do away with the other regulators

still a bit worried about possibly having to many amps

bert

ps is there a spell check on this site

[Denford Admin]

a pc power supply would need to be modified if using it as a standalone supply

You may have to short a couple of pins to make the PSU power up and the unit may not run without a load, ie, something connected to it - hence the load resistor fitted in these links:
http://web2.murraystate.edu/andy.batts/ ... SUPPLY.HTM
http://www.smpspowersupply.com/connectors-pinouts.html

ps is there a spell check on this site

There is no spell check in this site, but you can always try an online spellchecker like this first: http://www.spellcheck.co.uk/

still a bit worried about possibly having to many amps

Can you have too many amps ?
It's better to be over-rated, than under... if you're worried about it burning things up, then limit the current with the correct size fuse or circuit breaker.