Connection Fault Handling

When the connection between an owner-controller and output module breaks, the output can behave in the following ways depending on how the Output State in Communication Fault Mode parameter is configured:

Hold Last State – It causes the output to remain at the last value that is sent from the controller before the connection fault occurs.
User Defined Value – It forces the output to transition to a specific, user-defined value.

The output remains at that state value until the following occurs:

The connection to the controller is re-established.
The duration expired, which is based on the value that is defined in the Communication Fault Mode State Duration.

If you configure the output to transition to a specific value after the connection breaks, you must define how long the output remains at the specified value before it transitions to a Final Communication Fault State Value.

You can configure the output to remain at the specific value for the following times:

Forever
1 second
2 seconds
5 seconds
10 seconds

After the Communication Fault State Duration time expires, the output transitions to user defined Final Communication Fault State Value.

The Final Communication Fault State Value defines the value to which the output goes after the Communication Fault State Duration time expires.

When communication fails in Program Mode, the output can behave in the following ways, depending on how you configure the When Communication Fails in Program Mode parameter:

Leave Outputs in Program Mode State – It causes the output to behave as defined by the Output State in Program Mode selection.
Change Outputs to Communication Fault Mode State – It causes the output to behave as defined by the Output State in Communication Fault Mode selection.

Once the connection between the owner-controller and output module is re-established, the output resumes normal operation if the controller is in Run mode or goes to the configured Program Mode state if the controller is in Program Mode.