Rockwell Automation 1394 SERCOS Interface Multi-Axis Motion Control System - Manual (Page 48)

Publication 1394-IN024B-EN-P — February 2004
2-12 Troubleshooting Your 1394 SERCOS Interface System
Troubleshooting General
System Problems Use the tables below for troubleshooting general system faults.
Condition: Potential Cause is: Possible Resolution is:
Axis or System runs
uncontrollably
The position feedback device is incorrect or open. Check wiring.
Unintentionally in torque mode.
Check to see what primary operation mode
was programmed.
An internal malfunction exists. Replace system or axis module.
Axis or System is unstable
Motor tuning parameters are set too high. Run auto tune.
Position loop gain or position controller accel/decel rate is
improperly set.
Run auto tune.
Improper grounding or shielding techniques are causing noise to
be transmitted into the position feedback or velocity command
lines, causing erratic axis movement.
Check wiring and ground.
Motor Select parameter is incorrectly set (servo motor is not
matched to 1394). • Check setups.
• Run auto tune.
You cannot obtain the motor
acceleration/deceleration
that you want
Torque Limit parameters are set too low. Verify that current limits are set properly.
Motor Select parameter is incorrectly set.
Program the correct motor and run auto tune
again.
The system inertia is excessive.
• Check motor size vs. application need.
• Review servo system sizing.
The system friction torque is excessive. Check motor size vs. application need.
Available current is insufficient to supply the correct accel/decel
rate. • Check motor size vs. application need.
• Review servo system sizing.
Acceleration parameter is incorrect.
Verify parameter settings and correct them,
as necessary.
Velocity Limit parameters are incorrect.
Verify parameter settings and correct them,
as necessary.
Motor does not respond to a
Velocity Command
Check for possible faults.
Verify parameter settings and correct them,
as necessary.
The axis cannot be enabled for 1.5 seconds after disabling.
Disable the axis, wait for 1.5 seconds, and
enable the axis.
Enable signal has not been applied or the enable wiring is
incorrect. • Check the controller.
• Check the wiring.
The motor wiring is open. Check the wiring.
The motor thermal overload has tripped.
• Check for a fault.
• Check the wiring.
The motor has malfunctioned. Repair or replace the motor.
The coupling between motor and machine has broken (i.e., the
motor moves, but the load/machine doesn’t).
Check and correct the mechanics.
Primary operation mode is set incorrectly. Check and properly set the parameter.
Velocity limit parameters are set incorrectly. Check and properly set the parameter(s).
The axis module has a malfunction. Replace the axis module.