YASKAWA E-V Series User Manual page 317

9 Troubleshooting
Problem
Linear
Servomotor
Moves
Instantaneously,
and then Stops
(cont'd)
Linear
Servomotor
Speed Unstable
Linear
Servomotor
Moves
Without
Reference
Input
DB (dynamic
brake) Does Not
Operate
Abnormal Noise
from Servomotor
9-24
Probable Cause
Linear scale counting up direction
and linear servomotor coil assembly
forward direction do not agree.
Polarity detection is not performed
correctly.
Wiring connection to servomotor is
defective.
Speed control: Speed reference
input is incorrect.
Force control: Force reference input
is incorrect.
Speed reference offset is error.
Position control: Reference pulse
input is incorrect.
A SERVOPACK fault occurred.
Linear scale counting up direction
and linear servomotor coil assembly
forward direction do not agree.
Polarity detection is not performed
correctly.
Improper parameter setting
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
Investigative Actions
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 connection of power lead
(phases U, V, and W) and encoder
connectors.
Check V-REF and SG to confirm if
the control method and the input are
agreed.
Check T-REF and SG to confirm if
the control method and the input are
agreed.
Check if the SERVOPACK offset is
adjusted incorrectly.
Check Pn200.0 reference pulse
form or sign + pulse signal.
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.
Corrective Actions
Change the setting of Pn080.1
(Motor Phase Selection).
Match the linear scale direction and
coil assembly direction.
Correct the settings for the polarity
detection related parameter.
Tighten any loose terminals or con-
nectors.
Correct the control mode selection
parameter, or the input correctly.
Correct the control mode selection
parameter, or the input correctly.
Adjust the SERVOPACK offset cor-
rectly.
Correct the control mode selection
parameter, or the input correctly.
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.