Rockwell Automation 1771-IFF/A,D17716.5.116 FAST ANALOG INPUT MODULE - Manual (Page 17)

RUN
FLT
10528ĆI
FAST
ANALOG
(12 BIT)
Chapter
2
Publication 1771Ć6.5.116 - July 1996
Troubleshooting Your Input
Module
In this chapter, we describe how to troubleshoot your fast analog
module by:
•
observing the indicators
•
monitoring status bits reported to the processor.
•
checking module operation
•
checking for common mode voltages
•
isolating a bad input
At power-up, the module momentarily turns on the red indicator as a
lamp test, then checks for:
•
correct RAM operation
•
firmware errors
Thereafter, the module lights the green RUN indicator when
operating without fault, or lights the red FAULT indicator when it
detects fault conditions. The module also reports status and specific
faults (if they occur) in every transfer of data (BTR) to the PC
processor. Monitor the green and red indicators and status bits in
word 1 of the BTR file when troubleshooting your module.
Diagnostic Bits Reported By the Analog Input Module
Diagnostic bits in the read block transfer status words provide
diagnostic capabilities.
Word 1 provides power-up and valid data status. Words 2, 3 and 4
provide channel data status.
If a module on-board self test fault occurs, block transfers will be
inhibited, the red fault (FLT) will light, and the green run (RUN)
light will go out.
Word 1
Diagnostics word 1 is the first data word in the read block transfer
file for transfer to the central processor. It contains a power-up bit
(bit 00) that is set (1) when the module is first powered up. It is reset
(0) after a write block transfer. It also contains an under-range or
over-range bit (bit 01) that is set when any input is under or
over-range.
Chapter Objective
Diagnostics Reported by
the Module