IFM Electronic AC2255 Montageanleitung Seite 6

Addressing
At the factory the address is set to 0.
Addressing with the addressing unit AC1144
The mounted and wired module can be addressed with the addressing
cable (E70213) via the addressing socket.
Only address via the addressing socket when disconnected.
If the slave is used with a master of the new generation (version 2.1),
an address between 1A and 31B can be selected by means of the
addressing unit AC1144.
If a slave with the ID code "A" (extended addressing mode possible) is
used with a master of the first generation (version 2.0), the parameter
P3 must be 1 and the output bit D3 = 0*. The output bit D3 must not
be used.
If a slave with the ID code "A" (extended addressing mode possible) is
used with a master of the first generation (version 2.0), an address bet-
ween 1 and 31 must be assigned to this slave.
* default setting
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