Basic Questions about Steppers, Power Supplies, etc.

[Tom Kay]

Hi All;

I have some questions related to my drivers, power supplies and steppers. I hope someone can help.

I bought a kit, years ago, from Dan Mauch's Camtronics. It included 3 Italian stepper motors, bipolar, rated at 521 oz-in. 8 wire.

I have a diagram which shows series and parallel connection options, so I understand that. What I am not sure of, is this:

1. They appear to be rated at 3.29 amps. Does this mean each set of windings within the motor? I'd have them wired in series, likely. Would I actually need a power supply that output much more than 3.29 amps, for each motor?

2. I don't know what the voltage is of these motors. I suspect it's low, something like 2 or 3 volts. I don't understand why a stepper can be rated at 2 or 3 volts, yet they are suppose to run on 36VDC. Can someone explain that? Dan Mauch's kit instructions stated 36VDC MAX.

I think that's it for the moment, but any other basic info about steppers and power supplies would be greatly appreciated. I guess I'm just trying to power the motors with the correct power, and I don't know what happens if the supplies are rated too low. Blown supply fuse? Melted transformer secondary winding?

Thanks, Tom.

[BackyardWorkshop]

Hi Tom - I'm no expert but I think you'd need a power supply that could handle all three motors running at once - some something in the 10 amp range?

I also think the higher the voltage the better your motors will perform - so I'd go for near the max rating - again I'm no expert so maybe someone will chime in that knows for sure

[Tom Kay]

Thanks Geeks;

I'm starting to hear that from a few sources, so it looks like you're generally right. It's just odd that steppers, rated at 1.5 VDC take 36 VDC to power.

However, I won't fight it. I'll just roll with it.

Tom.

[James Newton]

The higher supply voltage is regulated down to the correct current flow through the motor windings by the driver. Having a higher voltage allows the driver to get the current flow to the desired value quicker. Think of it like this: If you have a /really/ long garden hose, and you want a trickle of water out the far end, you can supply a trickle at the valve and just wait... eventually, the water will trickle out the other end. But if you want that trickle NOW, you turn the water value on full, then wait for the water to start coming out the end before you turn it down.