Omron R88A-MCW151-DRT-E Operation Manual page 244

Problems and Countermeasures
No. Problem
28 Motor rotation is The parameters are set incor-
unstable. rectly.
29 The Servo Motor power lines
and encoder lines are wired
incorrectly.
30 There is eccentricity in the cou-
plings connecting the Servomo-
tor axis and the mechanical
system. There may be loose
screws or load torque fluctua-
tion due to the meshing of pul-
ley gears.
31 The gain adjustment is insuffi-
cient.
32 The wrong Servomotor is
selected (so it cannot be
adjusted).
33 The Servomotor bearings are
damaged.
34 The Servomotor windings are
disconnected.
35 Vibration is Inductive noise is being gener-
occurring at the ated.
same frequency
as the application
frequency.
36 The control signals are not
properly grounded.
37 Twisted-pair or shielded cable
is not being used between the
MC Unit and other devices.
Probable causes Items to check
Check the MC Unit parameters
with Motion Perfect.
Check the Servo Motor power
lines and encoder lines.
Check the machinery. Try turn-
ing the motor with no load (i.e.,
with the machinery removed
from the coupling).
---
Check the torque and inertia
ratings and select another Ser-
vomotor.
Turn OFF the Servo Driver
power. If the Servomotor has a
brake, turn ON the brake power
supply and release the brake,
and then manually turn the
motor's output axis with the
motor's power line discon-
nected (because the dynamic
brake may be applied).
With a tester, check resistance
between the Servomotor's U, V
and W power lines. There
should be a proper balance
between the line resistances.
Check whether the Servo Driver
control signals are too long.
Check whether the control sig-
nal lines and power lines are
bundled together.
Check whether the control sig-
nal shield is properly grounded
at the Servo Driver.
Check whether the control sig-
nal lines are in contact with
ground.
Check whether twisted-pair
cables are used for the encoder
signals and speed references,
and whether the cables are
shielded.
Section 8-3
Remedy
Set the parameters correctly
and modify the initialisation
program accordingly.
Correct the wiring.
Adjust the machinery.
Execute Servomotor autotun-
ing.
Manually adjust the Servo-
motor gain.
Adjust the servo control
parameters with Motion Per-
fect.
Change to a suitable Servo-
motor.
Replace the Servomotor.
Replace the Servomotor.
Shorten the control signals.
Separate the control signal
lines and the power lines.
Use a low-impedance power
supply for the control signal
lines.
Correct the wiring.
Use twisted-pair and shielded
cable as in the wiring exam-
ples.
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