Time-of-day synchronization roles of the communications module
With the time-of-day synchronization parameters, you specify the role of the communications module in the forwarding of time-of-day frames.
Depending on the mode of the module on PROFIBUS, the following synchronization roles can be set:
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The communications module is passive node on PROFIBUS (for example DP slave):
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Slave
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None
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-
The communications module is an active node on PROFIBUS:
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Master
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Slave
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None
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Meaning of the parameters
The parameters of the time-of-day synchronization have the following meaning.
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Type of synchronization
The parameter specifies the synchronization role:
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Slave
The CM clock is synchronized with another clock. The synchronization frames come from PROFIBUS. With this type of synchronization, the CM forwards the time-of-day frames to the station at a fixed interval.
Within the S7 station, there may be only one time-of-day slave.
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Master
The clerk of the communications module as master sends time-of-day frames to the PROFIBUS network.
If the synchronization type "Master" is set, the interval for outputting time-of-day frames can be selected.
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None
There is no synchronization.
If more than one module with a clock is present within a network, you need to specify which module will act as the time master and which as the time slave for time-of-day synchronization purposes. There can only be one time-of-day master.
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Update cycle
With the synchronization role "Master", the parameter defines the update interval at which the time-of-day frames are output to the network.