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Figure B.3– One sided OA in bidirectional safety communication

In the scenario of Figure B.3, an operator acknowledgment activated at controller A suffices for re-establishing the bidirectional connection. Both sides will cease delivering fail-safe values and continue sending process values. This is accomplished by connecting OperatorAckProvider with OperatorAckConsumer at the SafetyConsumer of controller B. Activating operator acknowledgment at controller B is not possible in this scenario.