hello,

Could I use a PS that is used for a printer for my:--

The XS-3525/8S-4 Stepper Motor Driver Board
The Perfect Choice For Your Sherline or Taig Four Axis CNC Retrofit

Four axis bipolar drive
±2.5 Amp/Phase PWM controlled drives
up to 35 Volt (w/BEMF)
FULL, HALF, QUARTER, & EIGHTH step/Full Step .

The PS that I would like to use is input 220 volte, output is 24VDC/5.0A .

I do not know if that would work.

any help of you will be appreciated.
thanks

Robhi

5Amps might just be on the low side depending on how many motors and their current ratings.
Hood

If three motors turn on simultaneously they could sink 7.5 amps - way beyond the capabilities of your power supply. If you have four motors - 10 amps.

You could be clever and only run programs that do not move more than 2 motors at once - but ?

A simple way I have my power supply is from two 12 volt leisure batteries which I charge up now and then. The advantage with batteries is that the overall voltage is steady at 24 v (in series) , no matter what the current drawn way beyond the 10 amp mark. It is a bit expensive - about £80 (UK) but, I find, very simple.

I have the input protected by a diode bridge in case I connect them the wrong way round inadvertantly.

Hi, thanks for your replies.
the motor that i have are the followings:

220Ncm - 10mm Shaft - Hybrid Stepper Motor 

Arc Code   AC571157525M
Type   Hybrid Stepper
Holding Torque   220Ncm
Step Angle   1.8°
Rated Voltage   7.5V
Rated Current   2.5A/Phase
No. of Wires   8
Size   57x57x115mm
Shaft Dia.   10mm
Shaft Length (Front)   30mm
Shaft Length (Rear)   30mm
Net Weight   1.74kg

I would like to run the three of them at once ( as am not too clever to run only 2), they would be wired in bipolar parallel,
so as you said I might have a PS of 24VDC/7.25 Am or more.
Am I right?

Robhi

I think the accepted figure is 2/3 of the total motor current as you are unlikely to be using all 3 axis at full current at the same time. However I would still be wary of using a power supply that is borderline, best bet is to get yourself  a toroidal transformer, a rectifier and a capacitor and build yourself a power supply. Bob Campbell has a good pdf on how to work out the figure for the various components of a power supply, you will find it here http://campbelldesigns.com/files/power-supply-part-1.pdf

Hood

You are using the same motors as I am. They work very well. I run mine on 24 volts, they get slightly warm but not hot, even when stood a long time.

Unlike an ordinary motor, a stepper motor comsumes power even when stood - the current keeps the rotor fixed in the one position. I think your 5 amp supply will struggle. You will find that the voltage output will dip as the motors take power. The Stepmaster cards I used at first carried a warning not to let the voltage drop below 12v, or everything would overheat.

Try it and see - start by using only two motors connected and see how the supply voltage holds up.

hi,
thankx  for replies, they are great and useful.
thankx again
robhi