Rockwell Automation 1557 MEDIUM VOLTAGE AC DRIVE - Manual (Page 299)

TROUBLESHOOTING 10-57
1557-UM050F-EN-P – June 2013
# FAULT / ALARM PROBABLE CAUSE RECOMMENDED ACTION
42 RATED I FEEDBACK
WARNING 1. THE CURRENT FEEDBACK
SCALING IS OUT OF RANGE
1A. CHECK THE PARAMETER AND
ENSURE PROPER VALUES ARE
ENTERED FOR C. T. RATIO. (P149)
C. T. LINE BURDEN (P151).
B. CHECK THE PARAMETERS AND
ENSURE PROPER VALUES ARE
ENTERED FOR LEM RATIO (P150) AND
C. T. MOTOR BURDEN RESISTOR
(P152).
43 TACH ROTATION
WARNING 1. THE TACH FEEDBACK SIGNALS
FROM PHASE „A‟ AND PHASE „B‟
INTERCHANGED
1. CHECK THE CABLING FROM
TACHOMETER TO DRIVE AND
CORRECT THE WIRING.
44 MOTOR OVERSPEED 1. LOSS OF LOAD 1A. CHECK THE APPLICATION AND
CHANGE THE SPEED REGULATOR
BANDWIDTH.
B. CHECK THE PARAMETER (P185) FOR
MOTOR OVERSPEED TRIP AND
INCREASE THE VALUE AS REQUIRED
BASED ON THE APPLICATION.
45 LINE HARDWARE
WATCHDOG
MOTOR HARDWARE
WATCHDOG 1. DRIVE CONTROL BOARD
HARDWARE FAILURE
2. DEFECTIVE EPROMs
1A. REPLACE DRIVE CONTROL BOARD
B.
ENSURE THAT EEPROM‟S ARE
INSTALLED CORRECTLY IN CORRECT
SOCKETS (EEPROM‟S INSERTED
BACKWARDS WILL NO LONGER BE
USABLE)
2A. REPLACE EEPROMs
46 LINE SOFTWARE
WATCHDOG,
MOTOR SOFTWARE
WATCHDOG 1. DRIVE CONTROL BOARD
HARDWARE FAILURE
2. FIRMWARE BUG
1A. REPLACE DRIVE CONTROL BOARD
B. RESET FAULT AND RESTART
2A. IF FAULT PERSISTS, ASK FACTORY IF
FIRMWARE UPDATE WILL ELIMINATE
PROBLEM
47 LINE SOFTWARE
OVERCURRENT,
MOTOR SOFTWARE
OVERCURRENT,
MOTOR HARDWARE
OVERCURRENT 1. OVERCURRENT TRIP
PARAMETERS SET TOO LOW
RELATIVE TO TORQUE LIMIT
2. CURRENT REGULATOR IN LIMIT
3. FLUX REGULATOR IN LIMIT
4. SHORTED THYRISTORS
1A. OVERCURRENT TRIP PARAMETERS
SHOULD BE INCREASED IF TORQUE
LIMIT INCREASED ABOVE DEFAULT
SETTING.
2A. IF LINE FIRING ANGLE IS STUCK AT
ADVANCE LIMIT (8 DEGREES),
CURRENT CONTROL MAY BE LOST.
INCREASE LINE VOLTAGE OR
DECREASE MOTOR FLUX COMMAND.
3A. IF MAGNETIZING CURRENT (LX)
COMMAND IS STUCK AT EXCITATION
LIMIT, CONTROL OF MOTOR VOLTAGE
IS LOST. INCREASE EXCITATION
LIMIT PARAMETER
4B. RESTART DRIVE TO ALLOW STARTUP
DIAGNOSTICS TO DETECT ANY
SHORTED THYRISTORS.