RE: stepping motor driver, 8-pack, Phytron-ECT

[Mark Rivers <rivers@cars.uchicago.edu>]

> Phytron claims that using appropriate shielding of the cables 
> avoids noise.
> I have not heard such about the ACS microstepper.

The ACS microstepper with shielded cables can be used with sensitive
detectors.  It's hard to see how their chopper would differ significantly
from ACS's in this regard.

> StepPack runs hot at > 5 Amps running current, requires 
> additional cooling which is provided within the chassis of Phytron. For
StepPack 
> it takes extra space.

I run lots of motors at 5-6 amps with no additional cooling.  What's the
evidence that it's required?

> The same is true for the power supply. ACS PS takes as much 
> space as a driver rackmount, therefore, requires taller racks. ACS PS
supplies 
> 25 Amps, while Phytron build-in PS provides 20 Amps for the ZSO.

One 5 foot rack holds 40 motors worth of ACS drivers plus power supplies.
It's pretty compact.  One rack is enough for our typical stations, since we
use the (much cheaper) University of Chicago driver boxes for little motors
like slits and K/B mirror benders.

Mark