Siemens SIMATIC S7-400 Hardware And Installation Manual page 59

Default Addresses of Analog Modules
On the S7-400, the default addresses for analog modules start from 512 (first slot
in the central rack which is usually occupied by the power supply module) up to
1600.
The algorithm used to calculate the default address of an analog module is:
Default address = (slot number - 1) x 64 + 512
Example
The default address of an analog module in the 6th slot is as follows:
Default address = (6 - 1) x 64 + 512 = 832
S7-400 and M7-400 Programmable Controllers, Installation Manual
C79000-G7076-C424-01
www.gkbpx.com
Addressing the S7-400
3-5