Rockwell Automation 1747-ASB Remote I/O Adapter - Manual (Page 143)

Publication 1747-UM006B-EN-P - June 2003
Differences Between the 1747-ASB Module and the 1771-ASB Series C Module B-3
Inserting and Removing I/O
Modules Under Power
(page 6-9)
In most cases, inserting or removing I/O modules while under power
does not cause a 1771-ASB error.
Whenever the 1747-ASB module is not faulted, inserting or removing
I/O modules under power does cause a 1747-ASB error.
Starting Logical Group
Number Selection
(page 4-4) In the RIO link system, only even numbered logical group numbers
(0, 2, 4, or 6) are valid.
The 1771-ASB module limits the allowable starting logical group
numbers based on the selected addressing mode and chassis size.
The 1747-ASB module allows virtually any group number to be
selected. The exception is when 1/2-slot addressing and discrete
mode is selected. Then, only logical groups 0 and 4 can be used.
Specialty I/O Module Image
Mapping and Control
(page 4-13) The 1771-ASB module maps all discrete I/O modules using discrete
transfers; data is exchanged with the scanner using RIO discrete
transfers on the RIO link. All specialty (Intelligent)
(1)
I/O modules are
block transfer mapped, data is exchanged with the scanner using RIO
block transfers.
The 1747-ASB module handles discrete modules the same way the
1771-ASB module does by using RIO discrete transfers.
ATTENTION
!
Disconnect power to the 1771- or 1747-ASB
chassis before attempting to insert, remove, or
wire any I/O modules.
(1) An Intelligent I/O module is a 1771 nondiscrete I/O module.
IMPORTANT
If you are only using discrete modules, the 1771-ASB
and 1747-ASB modules mapping and control are
identical.