Omron R88D-KTA5L User Manual page 586

11-4 Troubleshooting
Symptom
The Servomotor
holding brake is
ineffective.
The motor does not
stop or is hard to stop
even if the operation
command (RUN) is
turned OFF while the
motor is rotating.
The motor is
producing unusual
noises or the
machine is vibrating.
(Continued on next
page)
11
The motor is
producing unusual
noises or the
machine is vibrating.
(Continued from
previous page)
11-25
Probable cause
Power is supplied to the holding
brake.
The load inertia is too large.
The stop circuit failed.
There are problems with the
machine's installation.
There is a problem with the
bearings.
The gain is wrong.
The Speed Feedback Filter Time
Constant (Pn103) is wrong.
Noise is entering into the control
I/O signal cable because the cable
does not meet specifications.
Noise is entering into the control I/O
signal cable because the cable is
longer than the specified length.
Noise is entering into the cable
because the encoder cable does
not meet specifications.
Noise is entering into the encoder
cable because the cable is longer
than the specified length.
Noise is entering into the signal
lines because the encoder cable is
stuck or the sheath is damaged.
Excessive noise on encoder
cable.
The FG's potential is fluctuating
due to devices near the
Servomotor, such as welding
machines.
Errors are being caused by
excessive vibration or shock on
the encoder.
The machine and the motor are
resonating.
OMNUC G5-SERIES AC SERVOMOTOR AND SERVO DRIVE USER'S MANUAL
Items to check
Check whether power is supplied to the
holding brake.
Check the following:
·Is the load too large?
·Is the motor rotation speed too high?
−
Check to see if the Servomotor's
mounting screws are loose.
Check whether the axes are misaligned in
the coupling.
Check whether the coupling is unbalanced.
Check for noise or vibration around the
bearings.
−
Check the value set in Pn103.
Check to see if the cable is a twisted-pair
cable or shielded twisted-pair cable with
core wires that are at least 0.08 mm dia.
Check the length of the control I/O signal
cable.
Check to see if it is a shielded twisted-pair
cable with core wires that are at least 0.12
mm dia.
Check the length of the encoder cable.
Check the encoder cable for damage.
Check to see if the encoder cable is
bound together with or too close to high-
current lines.
Check for ground problems (loss of
ground or incomplete ground) at
equipment such as welding machines
near the Servomotor.
There are problems with mechanical
vibration or Servomotor installation (such
as the precision of the mounting surface,
attachment, or axial offset).
Check to see if the machine is resonating. · Readjust the torque command
Measures
Configure a circuit that cuts power
supply to the holding brake when the
motor stops and the load is held by
the holding brake.
Review the load conditions, and
replace the Servomotor and Servo
Drive with appropriate models.
Replace the Servo Drive.
Retighten the mounting screws.
Align the coupling.
Adjust the coupling's balance.
Contact your OMRON dealer or
sales office.
Perform manual tuning.
Return the set to 0 (default set) or
increase the set value.
Use a control I/O signal cable that
meets specifications.
Shorten the control I/O signal
cable to 3 m or less.
Use an encoder cable that meets
specifications.
Shorten the encoder cable to less
than 50 m.
Correct the encoder cable's
pathway.
Install the encoder cable where it
won't be subjected to surges.
Ground the equipment properly
and prevent current from flowing
to the encoder FG.
Reduce the mechanical vibration
or correct the Servomotor's
installation.
filter time constant.
· If there is resonance, set the
Notch Filter 1 Frequency
(Pn201), Notch Filter 1 Width
(Pn202), and Notch Filter 1
Depth (Pn203).