Rockwell Automation 8520 9/Series CNC Integration Maintenance Manual Documentation Set - Manual (Page 751)

Section 15A
Troubleshooting the Control
15A-41
Faults
Axis Module
CNC display: Error Message
Description
GRND
FLT
Axix Module PowerFault (0:1,2,3,4)
The axis module hardware has faulted from a short duration over current
condition. If the output current exceeds a fixed level (Over 200% of axis
module rating for the 10 and 15 Kw modules and Over 300% for the 2, 3 and
5 Kw modules) this fault will appear. Typical causes are a shorted lead,
motor malfunction, or malfunctioning power IGBTs.
OVER
CRNT
Axis Module OverCurrent (0:1,2,3,4)
This axis module of your 1394 system has been requested to provide too
much current over an extended time period. This is typically caused by:
Accel/Decel command from the CNC is requiring peak current for an
excessive amount of time, the machine friction or inertial/viscous load is
excessive, the motor has been improperly sized, a short circuit exists across
the drive output terminals, logic supply circuits have malfunctioned, or AC
input is incorrectly wired.
BUS
FLT
Axis Module Buss Voltage Loss (0:1,2,3,4)
The DC bus supply to the axis module was lost or has fallen below 275VDC.
Check slider connections/termination strip or there could be a blown link fuse.
This condidtion also occurs in a systemE--stop state.
OVER
TEMP 1
Axis Module OverTemp (0:1,2,3,4)
The 1394 axis module contains a thermal sensor which senses the internal
ambient temperature. Causes could be: that the cabinet ambient
temperature is above the 70 degree C rating. The machine duty cycle
requires an RMS current exceeding the continuous rating of the axis module.
The airflow access to the 1394 is limited or blocked.
Faults
System Module
CNC Display error message
Description
BUSS
VOLTAGE ____
HIGH :
System Module Over Voltage (0)
The 1394 system module bus voltage exceeds the maximum operating
voltage. The DC power bus is continuously monitored. If it exceeds a preset
level (810 Vdc), an over voltage fault is sensed and the axis modules are
disabled. This can be caused by an under sized shunt requirement, shunt
regulator fuse has blown, the shunt regulator transistor has malfunctioned,
the power driver board is malfunctioning and incorrectly sensing the bus
voltage, the CNC acc/dec rate is incorrectly set, the input line voltage is
excessive, the system inertia is too high causing excessive energy to be
returned to the power supply bus, or a vertical axis with insufficient
counterbalancing is overdriving the servomotor and causing excessive
energy to be returned to the power supply bus.
LOW :
System Module Under Voltage
The 1394 system module voltage does not meet the minimum operating
voltage. The DC power buss shall activate the under voltage limit when the
bus drops to 275 VDC or less. It will clear at 300 Vdc. Typical causes
include low voltage on the three phase input. If any Phase is missing, the
“PhaseLoss”message will take priority.
BUSS
VOLTAGE ____
VALUE : Displays the value of the DC buss voltage in DC volts. Nominal
normal voltage is 600 V