YASKAWA E-V Series User Manual page 231

Problem Probable Cause
A SERVOPACK fault occurred.
Linear
Linear scale counting up direction
Servomotor
and linear servomotor coil assembly
Moves
forward direction do not agree.
Without
Reference
Input
Polarity detection is not performed
correctly.
Improper parameter setting
DB (dynamic
brake) Does Not
Operate DB resistor disconnected
DB drive circuit fault
Mounting not secured
Vibration source on the driven
machine
Noise interference due to incorrect
I/O signal cable specifications
Noise interference due to long dis-
tance of I/O signal cable
Noise interference due to incorrect
serial converter unit connection
cable specifications
Abnormal Noise Noise interference due to long serial
from Servomotor converter unit connection cable wir-
ing distance
Noise due to damaged serial con-
verter unit connection cable
Excessive noise to the serial con-
verter unit connection cable
FG electrical potential varies by
influence of such machines on the
servomotor side as welders.
SERVOPACK pulse counting error
due to noise
Excessive vibration and shock to
the serial converter unit
Serial converter unit fault
8.3 Troubleshooting Malfunction Based on Operation and Conditions of the Servomotor
Investigative Actions
Check if the SERVOPACK board is
damaged.
Check the directions.
Check if the value of Un004 (Elec-
trical Angle 2, angle from 0 (zero)
degree of phase-U) at an arbitrary
position is between ±10 degrees.
Check the setting of parameter
Pn001.0 (Servo OFF or Alarm Gr.1
Stop Mode).
Check if excessive mass, motor
overspeed, or DB frequent activa-
tion has occurred.
Check if DB circuit parts are faulty. Replace the SERVOPACK.
Check if there are any loosen
mounting screws.
Check the machine movable section
for foreign matter, damage or defor-
mity.
The specifications of input signal
wires must be:
Twisted-pair or twisted-pair
shielded wire with core
2
0.12 mm min. and tinned annealed
copper twisted wire.
The wiring distance must be 3 m
max. and the impedance a few hun-
dreds ohm max.
The specifications of encoder cable
must be:
Twisted-pair or twisted-pair
shielded wire with core
2
0.12 mm min. and tinned annealed
copper twisted wire.
The wiring distance must be 20 m
max.
Check if the serial converter unit
connection cable is not damaged or
bent.
Check if the serial converter unit
connection cable is bundled with
high-current line or near the high-
current line.
Check if the machine is correctly
grounded.
Check if there is noise interference
on the I/O signal cable from the
encoder.
Check if vibration from the machine
occurred or serial converter unit
installation is incorrect.
(Mounting surface accuracy, or fix-
ing.)
−
Corrective Actions
Replace the SERVOPACK.
Change the setting of Pn080.1
(Motor Phase Selection).
Match the linear scale direction and
servomotor direction.
Correct the settings for the polarity
detection related parameter.
Correct the setting of parameter
Pn001.0.
Replace the SERVOPACK, and
reconsider the load.
Tighten the mounting screws.
Contact the machine manufacturer.
Use the specified I/O signal cables.
Shorten the wiring distance for I/O
signal cable to the specified value.
Use the specified serial converter
unit connection cable.
Shorten the serial converter unit
connection cable wiring distance to
the specified value.
Modify the serial converter unit
connection cable layout.
Install a surge absorber to the serial
converter unit connection cable.
Ground the machine separately
from PG side FG.
Take measure against noise for the
serial converter unit wiring.
Reduce vibration from the machine,
or correct the serial converter unit
installation.
Replace the serial converter unit.
8
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