Experimental Physics and
Industrial Control System

Timo Korhonen <[email protected]> · Wed, 28 Mar 2001 17:52:47 +0200

Hi,

could somebody who has experience using servo motors with the OMS58 card
(servo version) and the motor record please help me? I just started with this
combination and I have some questions (I hope they are easy ones.)

When I try to drive the motor, regardless of to what direction I would like to
drive,
I seem to always get a positive drive voltage. I tried to put the command "BI"
to init
field (and also PREM field) to be sure that I have the correct (BIpolar) mode,
but it
had no effect (bipolar should be the default mode at power up anyway.)
The voltage ramp has the trapezoidal shape as expected.

The motor is configured for bipolar (-10V to 10V) range. When I move in open
loop
control, it turns always to the same direction regardless of what the move
direction
should be.
Enabling closed loop with CNEN causes the voltage to jump between +10 and -10 V,

more or less like a square wave (this is possibly understandable if I have the
wrong
phases from the encoders. I tried both, however.)  So, the motor card obviously
can
drive negative voltages.

Any ideas what might be wrong?

Another question: Does anybody have a utility to send commands directly to
the OMS58 from the vxWorks shell?

Timo

--
Timo Korhonen  PSI (Paul Scherrer Institut), SLS
               CH-5232 Villigen PSI
               tel + 41- 56 3103262  fax + 41 - 56 310 3151
e-mail:        [email protected]

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System