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Entry type: FAQ Entry ID: 17521938, Entry date: 10/30/2003

Time synchronization in the SIMATIC environment via MPI-Subnets

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How do I execute a Time synchronization via the MPI-Subnet?

A time synchronization can be executed via all 3 great product families, SIMATIC S7 and PC in the SIMATIC spectrum. An example of a time synchronization via MPI is described in this FAQ.

Settings in the CPUs of the S7-300/400
The CPUs of the S7-300/400 family are parametrized in the HW config for the time synchronization. the properties of the CPU determine, how the time synchronization will be received or forwarded by the CPU. It can be configured as master (Time Sender) or Slave (Time Recipient). Moreover, it can be determined whether it is only synchronized PLC-internally (including the CPs, thus also requiring them for the CP-operation the) - or via it is also synchronized via MPI. The time ranges can reach from 1 second up to 24 hours.

Fig. 1: Time synchronization MPI

Configuration of the S7-300 CPU as a Time Master

Fig. 2: Example of an up to date S7-314 CPU as Time Master

Configuration of the S7-300 CPU as Time Slave

Fig. 3: Example of an up to date S7-314 CPU as Time Slave

Time Slave, Time Master, Time Sender, Time recipient, Time operation, Clock, SIMATIC Procedure, Set time

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