Rockwell Automation 1747-ASB Remote I/O Adapter - Manual (Page 68)

Publication 1747-UM006B-EN-P - June 2003
4-14 Configuration
1747-ASB Image Size Exceeds Slot Requirements
When there are not enough slots available to use the entire 1747-ASB
module image, output image data received by the 1747-ASB module
for the extra slots is ignored. All input image data sent to the scanner
for the extra slots is zero.
One Slot of Pair is Present, and 1747-ASB Module Image is
Available for Both Slots
When one slot of a pair is present and 1747-ASB module image is
available for both slots, the single slot can use the extra image space.
1747-ASB Module
0 1 2 3 4 5 6 Slot Number
Group 0 Group 1 Group 2 Group 3
Not Used Not Used
Group 4 Group 5 Group 6 Group 7
8 Logical Groups
Using 1-slot addressing and a 7-slot
chassis, six slots are available for I/O
modules. Because the image size is 8
logical groups, 2 logical groups are not
used. When there are not enough slots
available to use the entire 1747-ASB
module for the extra slots is ignored. All
input image data sent to the scanner for
the extra slots is zero.
4 Logical Groups
1747-ASB Module
0 1 2 3 Slot Number
Group 0 Group 1 Group 2 Group 3
Using 1-slot addressing and a 4-slot
chassis, three slots are available for I/O
modules. Because the image size is 4
logical groups, 1 logical group is not
assigned to a slot. Since slot 4 is not
present, the module in slot 3 can use both
logical groups assigned to the slot pair.
This could be done by installing a 32-point
input module in slot 3.