User`s manual

Troubleshooting
9
9-4
9. Troubleshooting
Symptom Possible cause Checkpoint Action
Robot
motion is
unstable.
Large load variation • Check the load variation.
• Check the capacity calculation.
• Reduce the load variation.
• Increase the capacity.
Large backlash of the
mechanical system
Check the backlash. Reduce the backlash.
Improper control gain Check the parameter settings. Readjust the control gain.
Signal cable or position
sensor cable intersects
the main circuit cable.
(These are in the same
cable duct.)
Check the routing of the signal cable and
position sensor cable.
Separate the signal cable and
position sensor cable from the
main circuit cable.
Shield wire of the
position sensor cable is
not connected.
Check the shield wire connection on
position sensor cable.
Connect the shield wire of the
position sensor cable correctly.
Robot driver failure
(Position sensor
failure)
• Check the power module. (Refer to
Chapter 7, "Maintenance and
Inspection".)
• Check the position count function, by
viewing the present position monitor
d-08.
If the robot driver is defective,
replace or repair it.
Offline auto-tuning
mode is set.
Check if the "Auto tuning mode" (FA-10)
parameter is set to "non".
Set FA-10 to "non".
Robot
speed
does not
increase.
Speed limit is applied. • Check the parameter settings (Fb-20
and Fb-21).
Set the speed limit value
correctly.
Torque limit is in effect.
(Wrong polarity)
• Check if the TL terminal is ON, by
viewing the Input terminal monitor d-05.
• Check if the setting is correct.
• Disconnect the TL terminal.
• Correct the polarity setting.
• Correct the torque limit setting.
Incorrect command
speed setting
Check the speed command input by
viewing the Monitor d-00.
Correct the command setting.
Improper control gain Check if hunting occurs. Readjust the control gain.
Load is heavy. • Check the load.
• Check the calculated capacity.
• Reduce the load.
• Increase the capacity.
Brake is applied to the
robot.
Check the brake. Release the brake.