Rockwell Automation 1747-ASB Remote I/O Adapter - Manual (Page 69)

Publication 1747-UM006B-EN-P - June 2003
Configuration 4-15
Both Slots Of A Pair Are Available But There Is Only Enough
1747-ASB Module Image Space Available For One Slot
This condition only occurs in 1/2-slot addressing.
When both slots of a pair are available but there is only enough
1747-ASB module image space available for one slot, the lower
numbered slot uses the available image space. If a four word
specialty module (i.e., 1746-NI4) is installed in this slot and the
1747-ASB module is configured for the discrete specialty mode, a
1747-ASB error occurs.
DIP Switch SW3
Hold Last State (SW3-1)
SW3 switch 1 allows discrete outputs to remain in their last state when
certain, but not all, system faults occur.
Hold Last State DIP Switch Settings
ATTENTION
!
If switch 1 is set to the ON position, outputs
connected to this chassis remain in their last state
when a fault occurs and machine motion may
continue after fault detection. We recommend that
you set switch 1 to the OFF position to de-energize
outputs wired to this chassis when a fault is detected.
1747-ASB Module
0 1 2 3 4 5 6 Slot Number
Group 0, 1 Group 2, 3 Group 4, 5
6 Logical Groups
Not Used Not Used Not Used
Using 1/2-slot addressing and a 7-slot chassis, six
slots are available for I/O modules. Because the
image size is 6 logical groups, the last two logical
groups of the image can only be used by slot 3 (slots
4, 5, and 6 are ignored unless the module faults).
SW3
Hold Last State
4
1
23
5
6
7
8
O N
SW3
Do Not Hold Last State
4
1
23
5
6
7
8
O N