Siemens S7-400 Installation Manual page 71

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 Hardware and Installation
A5E00069481-04
Addressing the S7-400
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