Siemens Sinamics S110 Function Manual page 43

3. The Control Unit's PPI address is pre-set to "3" in the factory.
4. You should also set the bus address to "3" during setup, or under "Properties" in the drive
5. You must use a null modem cable to connect the PC (COM interface) to the Control Unit.
Function Manual
Function Manual, 01/2011, 6SL3097-4AB10-0BP3
unit's shortcut menu.
Figure 2-3 Setting the bus address
This interface must not be switched.
Commissioning preparations for PROFIBUS
2.3 Connection via serial interface
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