Rockwell Automation Logix5000 Controllers Controller Information and Status Programming Manual - Manual (Page 14)

Chapter 1 Connections
If communication with a module times out, the controller produces the following
warnings.
• The I/O status indicator on the front of the controller flashes green.
• A Warning ( ) icon shows over the I/O configuration folder and over the
device that has timed out.
• A module fault code is produced, which you can access through:
• Module Properties window for the module.
• GSV instruction.
To monitor the health of your connections, use a Get System Value (GSV)
instruction to monitor the Module object for either the controller or a specific
module.
If you want to Get this attribute Data Type Description
Determine if communication
has timed out with any
device
LEDStatus INT
For efficiency, use a
DINT as the
destination data type. Current state of the I/O status indicator on the front of the controller.
You do not enter an instance name with this attribute. This attribute applies to the entire
collection of modules.
Value
Meaning
0 Status Indicator off. No Module objects are configured for the controller
(there are no modules in the I/O Configuration section of the controller
organizer).
1 Flashing red. None of the Module objects are Running.
2 Flashing green. At least one Module object is not Running.
3 Solid green. All the Module objects are Running.
Determine if communication
has timed out with a specific
device
FaultCode INT
For efficiency, use a
DINT as the
destination data type. A number that identifies a module fault, if one occurs.
In the Instance Name, choose the device whose connection you want to monitor. Make sure
to assign a name to the device in the I/O Configuration folder of the project.
If Module_Status is any value other than 4, the controller is not communicating
with the module. See the following example.
14 Rockwell Automation Publication 1756-PM015F-EN-P – October 2014