Rockwell Automation 1771-IR Series D RTD Input Module User Manual - Manual (Page 47)

Chapter
7
Publication 1771Ć6.5.129 - March 2000
Troubleshooting
We describe how to troubleshoot your module by observing LED
indicators and by monitoring status bits reported to the processor.
At power–up, the module momentarily turns on both indicators as a
lamp test, then checks for
•
correct RAM operation
•
EPROM operation
•
EEPROM operation
•
a valid write block transfer with configuration data
Thereafter, the module lights the green RUN indicator when
operating without fault, or lights the red fault (FLT) indicator when
it detects fault conditions. If the red FLT indicator is on, block
transfer will be inhibited.
The module also reports status and specific faults (if they occur) in
every transfer of data to the PC processor. Monitor the green and
red indicators and the status bits in word 1 of the BTR file when
troubleshooting your module.
Indicators
RUN
FLT
RTD
INPUT
Green RUN LED
Red Fault (FLT) LED
This module uses a read block transfer to transmit data and to
monitor module and data status. Word 1 of the read block transfer
data file contains module status, power–up, and data out–of–range
information. Word 2 contains data polarity and overflow
information. Words 3 through 8 are data words.
Table 7.A shows indications and probable causes and recommended
actions to correct common faults.
Chapter Objective
Diagnostics Reported by
the Module