Why are identical operator messages generated with a new time stamp?
You create messages in message class "Operator messages" with the MESSAGE and ALARM_8P blocks. If there is a "HIGH" signal permanently at the message input of the block, the associated message is generated again with a new time stamp as soon as another message input receives a "HIGH" signal. This is a system property of the message class "Operator messages".
The message class "Operator messages" is defined as follows in WinCC:
- Messages without "gone" state
- Messages without acknowledgment
Each "HIGH" state of the block is entered in the operator activities log, as soon as a message is sent from the MESSAGE or ALARM_8P block through a 1/0 or 0/1 transition at any block input.
- A change in WinCC is not possible because of the missing "going" message.
Operation via an I/O field.
- A change in the AS block is not possible because neither the message class nor the WinCC acknowledgment behavior is known to the block algorithm.
Provide the input concerned with pulses when using the MESSAGE or ALARM_8P block for operator messages. A permanent "HIGH" signal is not permissible in this case.