Siemens SIMATIC ET 200S Operating Instructions Manual page 46

Application planning
3.4 Application of power modules
Placing power modules and connecting them to common potential
①
②
③
④
⑤
⑥
⑦
If you connect the AUX1 bus to common potential independently of the P1/P2 buses
(different voltages), there is no safe electrical separation (in accordance with EN 50178)
between the AUX1 bus and the P1/P2 buses.
Connecting different potentials to the AUX1 bus
Note
If you apply different potentials to the AUX1 bus within an ET 200S station, you must
separate the potential groups by means of a power module with the TM-P15S23-A0 terminal
module.
46
4
1 2
7
Interface module
Power module
Terminating module
Potential group 1
Potential group 2
Potential group 3
Supply voltage 1
WARNING
5
2 2
8 9 7
⑧ Supply voltage 2
⑨ Supply voltage 3
⑩ Protective conductor
⑪ Additionally required voltage
⑫ P1/P2 power buses
⑬ AUX1 bus
Operating Instructions, 08/2008, A5E00515771-06
6
3
ET 200S