Rockwell Automation 1771-KA2 Communication Adapter Module - Manual (Page 67)

Status Words
Chapter 6
6-3
As Figure 6.1 shows, the selection of a START bit in the program not only
causes a corresponding DONE bit to be controlled in the same word, but
also causes REMOTE and LOCAL FAULT bits to be controlled in the
next data table word. A REMOTE FAULT and LOCAL FAULT bit are
controlled for each command. For a command, the position of each of
these FAULT bits within their respective bytes corresponds directly to the
position of START and DONE bits for that command.
The KA2 controls REMOTE and LOCAL FAULT bits. The module sets a
FAULT bit ON when a command cannot be executed due to a
hardware-related fault either between stations or between the remote
station communication adapter module and its station processor.
Figure 6.2 summarizes the significance of these bits.
Figure 6.2
REMOTE/LOCAL FAULT Bit Significance
AC FUSE
PLC
2/20
Local Fault
Possible Sources:
•
Disconnected data highway cable
Power off at receiving station
interface module
Unused remote staiton no. address
Station interface moduel at local
or remote station has disconnected
itself as a result of link monitoring
Automatic timeout at sending
station
•
•
•
•
AC FUSE
PLC
2/20
Remote Fault
Possible Sources:
Remote station processor
in program load (or prog)
mode
•
Command not executed due to
module switch setting at
receiving station
Fault at remote station processor
Power off at remote station processor
Disconnected data highway/processor cable
Error detected in communication zone of
program at remote station proccessor
•
•
•
•
•
Processor
Processor
Receiving (Remote) Station
10866-I
Sending
Station
REMOTE/LOCAL FAULT Word