Siemens SINAMICS S120 Function Manual page 511

Topology
Figure 8-23
Master/slave operation can be implemented for a maximum of four Active Line Modules.
Drive functions
Function Manual, (FH1), 04/2014, 6SL3097-4AB00-0BP4
Topology structure and communications network based on PROFIBUS for master/slave
operation with redundant infeeds (four infeed trains)
8.9 Master/slave function for Active Infeed
Function modules
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