Is a 5.0 Amp power supply too small?

[SpookyDad]

If the Xylotex board can deliver 2.5 amps to each motor and we have a 3 axis kit, wouldn't a 5.0Amp power supply be undersized? Shouldn't we be looking for a 7.5 amp power supply?

[joecnc2006]

Originally Posted by SpookyDad If the Xylotex board can deliver 2.5 amps to each motor and we have a 3 axis kit, wouldn't a 5.0Amp power supply be undersized? Shouldn't we be looking for a 7.5 amp power supply?

I would go with 10amp, that what i use. from MP&J i think it is, 24vac 10a for 17.99.

Joe

[NC Cams]

The continuous current rating may be less than momentary spikes that occur. I'd concur with the 10 amp recommendation.

It is better to be looking AT the power being there if you need it than looking FOR the power should the need arrise.

[ger21]

With a bipolar chopper drive, like the Xylotex and Gecko's, the motors never need more than 2/3 the rated current, and usually use much less. 2/3 of 2.5 x 3 is 5 amps. If al the motors drew the maximum current at the same time, you'd theoretically need 5amps. Xylotex sells their kit (or used to, haven't checked lately) with a 4.5amp supply. He has said many times on their support group that it is more than adequate.

But, having a larger supply won't hurt anything. I have a 24V 12amp supply I got on Ebay for $5.

[SpookyDad]

Joe do you have a part number for the 24v 10a power supply?
I can't find it on MJP&A's site. Maybe I am searching for the wrong thing.

[SpookyDad]

Ok I found the following transformer: http://www.mpja.com/category/Transformers/24V_CT_(12-0-12)10A_TRANSFORMER_7846_TR.asp

Can this be used without any additional components?

[ger21]

Originally Posted by SpookyDad Ok I found the following transformer: http://www.mpja.com/category/Transformers/24V_CT_(12-0-12)10A_TRANSFORMER_7846_TR.asp Can this be used without any additional components?

You'd also need a bridge rectifier and capacitor. But, a 24V transformer will give you about 33V DC, which is too close to the Xylotex limit. It will probably damage the drive. The Xylotex should be run at no more than 28-30V MAX.

[SpookyDad]

Is there a tutorial/website/set of instructions on how the transformer/bridge rectifier/capacitor(s) would go together? I think this is (sadly) pretty basic stuff as far as electronics theory goes, but it is still over my head.

[NC Cams]

Go here:

http://www.campbelldesigns.com/files...ply-part-1.pdf

If you can't understand what's going on after reading the above, you probably shouldn't be messing with electronics....

[SpookyDad]

Ok that makes it a lot more clear. The article indicates, "...the value should never exceed 67% of the total...". So the 5.0 amps would be 2/3 of the 7.5 amps rated. I think I will buy the kit and mess around with building the 10 amp supply as a side project.