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

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

Folks,

Note that the Lincos drivers look nice, they are linear (quiet) and they can
microstep up to 20 microsteps/step.  However, they can only drive 2.5 amps
per phase.  If you want to drive larger motors you need to use the ZSO
drivers.  However, those are choppers, so they will probably not be
electrically quiet.

On our beamline >75% of the motors are more than 2.5 amps/phase, so ZSO's
would be needed.

Note also that on the Step-Pak you can mix and match different drivers
(microstepping, unipolar, bipolar) in a single chassis.  I don't think you
can do that with either proposed Phytron unit, so you would need a complete
rack to service a single microstepping motor.

If the issue is price we should we ACS to bid against Phytron and give us
quantity discounts like they are.  Their single unit prices are no better.

Mark