User manual

Troubleshooting
General Problems 5-2
Enhanced, Ethernet,
and ControlNet PLC-5
processors only
troubleshooting – Enhanced, Ethernet, and ControlNet PLC-5 processor general problems continued...
Indicator Color Description Probable Cause Recommended Action
PROC off processor in program load or TEST
mode or is not receiving power
Check power supply and
connections
Alternating Red and
Green
Processor in FLASH- memory
programming mode
Processor FLASH memory
checksum error
Contact your local A-B
representative for a field
firmware update
COMM off no transmission on channel 0 normal operation if port is
not being used
none
green (blinking) transmission on channel 0 normal operation if port
being used
none
FORCE amber (steady) SFC and/or I/O forces enabled normal operation none
amber (blinking) SFC and/or I/O forces present, but not
enabled
normal operation none
off SFC and/or I/O forces not present normal operation none
BATT off battery is good normal operation none
red (steady) battery low battery low Replace battery within 10
days (typical)
BATT
PROC
FORCE
COMM
PROG
RUN
R
E
M