Rockwell Automation 1794-ASB/E Remote I/O Adapter Module User Manual - Manual (Page 53)

Chapter
4
Publication 1794ĆUM009D-EN-P - April 2004
Troubleshooting
In this chapter, we tell you:
•
about the indicators on the module front plate
•
how to use the indicators for troubleshooting the module
Three conditions can cause the remote I/O adapter to declare a
communication fault.
•
no remote I/O (link) communication for more than 100ms
•
no commands issued to this address over the remote I/O link
within the last 255 link transactions
•
communication is lost to a module when Rack Fault Select is
enabled
When any of these conditions exist, the adapter will:
•
reset all digital outputs or leave them in their last state (depending
on the position of the last state switch, S2-1). Refer to page 2–9
for an explanation of analog module responses.
A communication fault will be automatically cleared by a command
from the processor if PRL (processor restart lockout) is not selected,
or by pressing the reset switch on the front of the module if PRL is
selected.
Adapter Fault
Local Fault
Adapter Active
ACTIVE PWR
AllenĆBradley
FAULT
LOCAL
FAULT
ADAPTER
Power ON/OFF
Reset Switch
Important: Cycling power to the adapter will also reset faults.
However, any queued block transfers will be lost, and
all outputs will turn off, regardless of the position of the
last state switch.
The module has indicators on the front plate as shown below. Use
these indicators for troubleshooting the module. The following tables
describes problems that may occur, probable causes, and
recommended courses of action.
Chapter Objectives
Fault Conditions
Troubleshooting with the
Indicator Lights