Slot Addressing

Slot Numbering

The 1747-ASB module is capable of controlling 30 slots. When expansion chassis

are used, the 1747-ASB module treats all of the I/O modules as if they are installed

in a single chassis.

The remote chassis and remote expansion chassis slots are numbered from 0 to 30.

The 1747-ASB module must reside in slot 0. Slots numbered 31 and above cannot

be used.

IMPORTANT Installing modules in slot 31 or above results in a module error.

Addressing I/O Modules

SLC and PLC processors address the I/O modules residing in the chassis by logical

rack and logical group. Slot addressing refers to how each chassis slot is assigned a

specific amount of the 1747-ASB module image. The amount depends on which

type of slot addressing you choose; 2-slot, 1-slot, and 1/2-slot addressing is

available, as shown below.

IMPORTANT Due to SLC and PLC addressing differences, when the 1747-ASB

module is used with an SLC processor, the image bit numbers are

0 to 7, 8 to 15 decimal. When the 1747-ASB module is used with

a PLC processor, the image bit numbers are 0 to 7, 10 to 17 octal.