If you implement both PLC and cabling redundancy, the enabler attempts to communicate over both cables to the current master PLC of the redundant pair. Once the enabler fails over to the secondary cable, it generates an alarm and updates the corresponding diagnostic point value. The enabler checks the failed primary cable periodically and automatically fails back to it when the cable is restored.

The enabler uses the following algorithm to determine which PLC and cable combination to use:

The enabler tries to communicate to the current master over its primary cable.

If that fails, the enabler tries to communicate to the current master over its secondary cable.

If that fails, the enabler tries to communicate to the current slave over its primary cable.

If that fails, the enabler tries to communicate to the current slave over its secondary cable.

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