What power supply i shoud choose??

[sierra]

Hi,

I need some addvise with power supply.

I have tachus42 designed driverboard and chopper board.

My motor are with next spec´s 2.1A 1.7mH 1.1 ohm has 8 wires.

i think that 24V coud be fine but how many Amps it shoud give? what you guy´s think?

Can i use pc supply +12 and -12 to create 24V that i shoud know if i use pc supply?

Best Regards

Jarkko From Finland

[project5k]

i'm not familiar with the boards that you are using, but i can tell you about pc powersupplies.. first, no you cant use the + and - to get your 24v.. if you look closely at the specs on most AT and ATX PSU's you will find that the - supply is very low current, on the ones that i have play'd with it is in the .5A range..

if you do some research you can find instructions to convert pc psu's for use as bench supplies, if you break the connection of the ground to the case, and to the ground side of the outputs, you can then daisy chain a couple of them to get your power, but be very carefull if you go this route, there are some large caps and high voltages in these things, that can really hurt or worse...

my suggestion would be to go to a more conventional type powersupply. you can get these on ebay for around $30 and up depending on the specs that you need..

as for current. i dont know about your boards again, but just for compairson.. the gecko's reccomend around 2/3 of the motor current per motor, so just for example, if your motors are 2.1A then that would be 1.4A per motor, then multiply by the # of motors that you have.. assuming 3 that would be 4.2A, plus a little safety margin, i would call it 5A... or thats my understand anyway.. i might be way off, but thats the math that i'm using to set mine up..

[sierra]

Thank for your reply!

I think i go first with pc Supply +12V i has rated max Amps of 8A

I use chopper board with power resistor witch gives that chopper current of 1.4A

will do some testing maybe it gives me enough speed newer Knows.

Jarkko From Finland

[project5k]

ok, gool luck and let us know how it works out.

[dertsap]

http://cgi.ebay.com/POWER-ONE-250W-2...QQcmdZViewItem

good deal on ebay if your interested
power-one makes some excellent and very expensive supplies
ive got three of those babies on my setup and i'm quite happy

[project5k]

i actually went with this...

http://cgi.ebay.com/ws/eBayISAPI.dll...MEWN:IT&ih=014

just seemed easy to me and cheap, and i can allways daisy chain 2 of them together if i wanted to double the V

[dertsap]

hubbard is great !
ive made a few purchases from them , nice stuff and reasonably priced

the power-one supplies can be run in series or parallel as well , i think the most i payed for one was 30 bucks plus shipping , ebays great !

[project5k]

well i got my parts in today.. sitting here playing with my new signal generator figuring out the winding ratios on the different taps to see what different voltages i can get out.. double check my math, i'm going on about a 10 year memory on this...
inputv * ratio= vac out on the transformer.. then... go through a bridge and into a cap and....
output vac * 1.303 = dc v out...

if thats right then playing with the different taps on this xfrmr i can get between 36.7 and 48.69vdc out...

wow, and i thought i was impressed with my little pc powersupply and able to max out mach at 270ipm, just not reliably.. with this powersupply i can increase the reliability of that 270ipm... now thats just splendiferious!