User Manual Owner's manual

3–20 Addressing Modes for Your Remote I/O
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Assigning I/O Rack Numbers with 1/2Ćslot Addressing
The following rules apply when you assign I/O rack numbers for
1/2-slot addressing:
• One assigned I/O rack number is made up of eight I/O groups
(Figure 3.18).
• The maximum number of I/O racks you can assign to the
different chassis sizes are:
one I/O rack to 1771-A1B chassis
two I/O racks to 1771-A2B chassis
three I/O racks to 1771-A3B chassis
four I/O racks to 1771-A4B chassis
• You can mix addressing methods in your remote system on a
chassis-by-chassis basis (1-slot and 1/2-slot addressing with
32-point I/O modules).
• You cannot assign one I/O rack number to more than one I/O
chassis when you select 1/2-slot addressing.
• Each I/O chassis begins an assigned I/O rack number. Make sure
that you set switches 7 and 8 of switch assembly SW1 to the ON
position when you select 1/2-slot addressing. The remote I/O
adapter module automatically assigns the next higher I/O rack
number(s) to the remaining I/O groups of the chassis.