www.baldormotion.com
Troubleshooting 7-5
MN1928
Symptom
Check
Motor runs
uncontrollably when
controller is switched
on.
Verify that the backplane (if used) and drive are correctly grounded
to a common ground point.
(Servo outputs only)
Check that the correct encoder feedback signal
is connected to the encoder input, the encoder has power (if
required, see section 5.2.12) and is functioning correctly.
Check that the drive is connected correctly to the NextMove ES and
that with zero demand there is 0 V at the drive’s demand input. See
section 6.5.1.
Motor runs
uncontrollably when
controller is switched
on and servo loop
gains are applied or
when a move is set
in progress. Motor
then stops after a
short time.
(Servo outputs only)
Check that the encoder feedback signal(s) are
connected to the correct encoder input(s). Check the demand to the
drive is connected with the correct polarity.
Check that for a positive demand signal, a positive increase in axis
position is seen. The
ENCODERMODE
keyword can be used to
change encoder input direction. The
DACMODE
keyword can be
used to reverse DAC output polarity.
Check that the maximum following error is set to a reasonable
value. For setting up purposes, following error detection may be
disabled by setting
FOLERRORMODE
to zero.
Motor is under
control, but vibrates
or overshoots during
a move.
(Servo outputs only)
Servo loop gains may be set incorrectly. See
sections 6.5.2 to 6.7.
Motor is under
control, but when
moved to a position
and then back to the
start it does not
return to the same
position.
Verify that the backplane and drive are correctly grounded to a
common ground point.
(Servo outputs only)
Using an oscilloscope at the backplane
connectors, check:
H
All encoder channels are free from electrical noise;
H
They are correctly wired to the controller;
H
When the motor turns, the two square wave signals are
90 degrees out of phase. Also check the complement
signals.
Ensure that the encoder cable uses shielded twisted pair cable, with
the outer shield connected at both ends and the inner shields
connected only at the NextMove ES end.
(Stepper outputs only)
The motor is not maintaining synchronization
with the NextMove ES drive output signals due to excessive
acceleration, speed or load demands on the motor.
Check that the acceleration, speed and load are within the
capabilities of the motor.
Servo Systems Co. • 115 Main Road • P.O. Box 97 • Montville, NJ,
07045-0097 • (973) 335-1007 • Toll Free: (800) 922-1103
Fax: (973) 335-1661 • www.servosystems.com
