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Entry type: Application example Entry ID: 25339612, Entry date: 04/27/2007

MICROMASTER: Parameter reading&writing of a MM4 using S7-300/400 (STEP 7 V5) with PROFIBUS Parameter (realtime clock)

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This application only applies to MICROMASTER 4



This application shows how the time (clock time) of the drive inverter can be synchronized with the CPU clock time - and how you can read-out the fault buffer and the clock time of the drive inverter.



All drive inverters have an internal time transmitter function that is used to time-stamp and log error conditions. However, there is no battery buffered realtime clock (RTC). The drive inverters can support a software-controlled RTC where the RTC must be set from the AOP or via an interface. When using the AOP, this synchronization is automatically carried-out. When using a serial interface, a request must be sent from the higher-level control to write to parameters.

This example shows how the time transmitter function of the inverter MICROMASTER 4 can be synchronized with the realtime clock of a CPU via PROFIBUS when the drive inverter is powered-up. An S7 project example has been written to achieve this. In the project, the realtime clock of the CPU is read-out and the time is written to parameter P2115 of the drive inverter. The project example also allows the fault buffer of the drive inverter to be read-out and the drive inverter to be controlled.




Content of Downloads


Documentation (German)
PDF_Echtzeituhr_V1_00.pdf ( 1691 KB )
Documentation (English)
Real Time Clock
PDF_Real_time_clock_V1_76.pdf ( 1620 KB )
Real Time Clock
MM4_Real_time_clock_76.zip ( 413 KB )



Version Date


V1.0 April 2007 first edition


Keywords: Realtime clock, MM4, Step 7, synchronizing


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