Rockwell Automation T3411 ICS Regent Monitored Digital Input Modules - Manual (Page 20)

Monitored Digital Input Modules (T3411)
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Industrial Control Services
During operations the input circuit is monitored for open
circuit and short circuit wiring faults. This bit is normally on
and turns off if either an open circuit or short circuit is
detected.
Line fault status is only reported through the Fault Name
variables. Line faults are not reported as a permanent I/O
module fault and do not turn on the associated system control
relay fault bit for the module. Line faults are not latched. If a
line fault condition returns to normal, the Fault Name
variable status also returns to normal.
Fault Name Description
This 40-character field provides a place to describe the input
point fault name definition. The description is used to help
document your system (it does not affect application program
operation).
Disable Fault LED
Marking the Disable Fault LED check box disables the fault
LED for this input point on the face of the input module.
Marking this box does not stop the module from line
monitoring the input circuit and updating the state of the
Fault Name variable, it only stops the module from displaying
line faults on the face of the input module. Line faults are still
reported to the Regent and are available to the application
program through the fault name variable.
This box can be checked for those input points that do not
have LMDs installed, or that are spare and have no field
switches connected. In this configuration the line fault LED
will always be off. If you do not check this box for input points
without LMDs installed or unconnected spare input points,
the line fault LED will always be on.
Programming
Inputs are referenced in the application program through the
tag names defined in the I/O Configuration Editor. When
current flows through the input (field switch closed) the input
is said to be on, or have a value of one. In ladder logic, the on
state would produce power flow in a normally open (N.O.)
contact.
Note: