Yaskawa YASNAC PC NC Maintenance Manual - Manual (Page 99)

PC NC Maintenance Manual Chapter 4: Troubleshooting
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The stopping position in which specified is differ (encoder method).
Cause and measures
The stopping position in which specified is differ (magnetic sensor method).
Cause and measures
Cause Measures
Stopping position command improper set-
ting Check that the position command is correct by the drive
state display (U3-04).
Binary and BCD command improper selec-
tion
Or, BCD command resolution improper
setting. Confirm the control parameter (C1-25) setting and refer to
the setting list.
C2-22 bit 3
C2-12
Reference point selection fault when posi-
tioning the incremental positioning. Confirm the control parameter (C1-25) setting and refer to
the setting list.
C2-22 bit 5
Load axis starting point position improper
setting Position by the starting position and measure position
accuracy.
Redo the tuning and reset the load axis starting point.
Encoder signal conductor disconnection /
the improper connection / the connector
omission. Check the encoder signal conductor wiring.
Improper drive by noise (encoder cable
characteristic defect) Check the encoder signal conductor is isolated from the
main circuit wiring and other power lines.
Check encoder cable specification (twisted-pair shield
wire) [recommended cable “KQVV-SW” by Fujikura-
Densen Co.]
Control card fault Exchange the control card with a non-defective one.
Cause Measures
Magnetic sensor / magneto mounting direction
is opposite. Check the installation of the sensor and magneto.
Magnetic sensor reading line disconnection /
connector omission Check the magnetic sensor single conductor wiring.
Orientation card fault Exchange the orientation card with a non-defective one.
Control card fault Exchange unit (exchange control card)