Allen-Bradley 1394 SERCOS, User Manual

Page: 176 / 301

Publication 1394-5.0 — May 2000
9-10 Troubleshooting
Understanding Analog Servo
System Module Faults
The faults that apply to the Analog Servo System’s system module
appear in the following tables.
Note: Although these faults are for the Analog Servo version, in many
instances, the descriptions, causes, and resolutions can also
apply to the GMC version. The fault messages, however, would
be different. Refer to the
GML Programming Manual
(publication 999-104) for more information.
Fault Message: Description: Potential cause: Possible resolutions:
Bus Config
The configured bus
voltage mode does not
match the hardware. The system module detected an incorrect
shunt module configuration (wrong shunt
installed).
• Verify that the shunt module is rated for
and compatible with your system
module.
Custom shunt parameters exceed the system
module shunt limits.
• Verify custom shunt parameters do not
exceed the system module limitations.
Bus Low Vlt
The DC power bus
activates undervoltage
limit when the bus drops
to 275V DC or less. It
will clear at 300V DC. The voltage on the 360/480V AC input power
is low.
Verify incoming AC voltage and change
the supply source, if needed.
Bus Ovr Vlt
The DC Power Bus is
continuously monitored.
If it exceeds a preset
level (810V DC), a fault
is sensed and the power
supply is disabled.
Bus Voltage Operation
Shunt turns on at
800V DC
Shunt turns off at
750V DC
Over voltage trip point
810V DC
Under voltage trip point
275V DC
Under voltage fault
clears at 300V DC
If this fault occurs when you power up the
system module with the M-contactor, the
power distribution impedance might be stiff or
line voltage might be too high.
• Perform line conditioning.
• Verify that line voltage is within
specifications.
The position controller acceleration /
deceleration rate is incorrectly set.
Change the command profile to reduce
speed or increase time.
The system inertia is too high causing
excessive energy to be returned to the power
supply bus.
• Change the command profile to reduce
speed or increase time.
• Use a larger external shunt resistor.
A vertical axis with insufficient
counterbalancing is overdriving the servo
motor and causing excessive energy to be
returned to the power supply bus.
• Use the external shunt resistor.
• Increase the mechanical
counter-balance on the machine.
Input line voltage exceeds the maximum input
voltage rating.
Verify incoming 360/480V AC input
voltage and change the supply source, if
needed.
Power Driver Board is malfunctioning and is
incorrectly sensing the bus voltage.
Replace the system module.
The shunt regulator or transistor has
malfunctioned.
Replace the system module.
External shunt regulator fuse has blown.
Check and possibly replace the shunt
resistor.
CAN Hdwr
SCANport hardware
error detected. The SCANport device or cable is faulty.
Check SCANport connections.
Cntctr Flt
Three-phase power is
either detected when it
shouldn’t be or not
detected when it should
be. The contactor is welded or failed to open.
• Correct wiring.
• Replace the contactor.
The input wiring to your contactor is incorrect. Correct wiring.
Cur Limit
The system module has
reach its current limit. The motoring/regenerative current produced
by the motor(s) and axis module(s) exceeds
the current limit allowed by the system
module.
• Increase system module size. The sum
of the axis modules continuous current
exceeds the system module current
limit rating.