Siemens SIMATIC S5 Manual page 306

System components
4)
(please enter order numbers)
Controller:
Power supply:
CPU:
Slot number:
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Version
Expansion unit:—
Power supply:
Interface module
Slot number:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Version
Have the drive specification% machine data and any machining programs ready
(see machine data planning or print out this data).
Make sure you know the jumper and switch settings on the module.
pair: -
7 - 3 9