Dip switch location (chapter 4), I/o module keying (page 4-21) – Rockwell Automation 1747-ASB Remote I/O Adapter User Manual
Page 144
Publication 1747-UM006B-EN-P - June 2003
B-4 Differences Between the 1747-ASB Module and the 1771-ASB Series C Module
If the 1747-ASB module is configured for the block transfer mode, it
handles all specialty I/O modules in the same manner as the 1771-ASB
module does by using RIO block transfers.
DIP Switch Location
(Chapter 4)
The 1771-ASB module has two DIP switches and uses one DIP switch
on the 1771 chassis.
The 1747-ASB module has three DIP switches.
I/O Module Keying
(page 4-21)
The 1771-ASB module uses the chassis hardware keying bands to
ensure the proper I/O modules are installed in the correct slot.
The 1747-ASB module uses a DIP switch setting and software to
ensure that the proper I/O modules are installed in the correct slots.
IMPORTANT
PLC processor control of 1771 and 1747 specialty I/O
modules on the RIO link is the same if the 1747-ASB
module is configured for RIO block transfer.
However, the I/O modules themselves are not
controlled in the same way.
For example, if a 1771-IFE analog input module is
used with the 1771-ASB module, RIO block transfers
are used to transfer the 1771-IFE image data between
the scanner and 1771-ASB module. In addition, the
1771-IFE module also receives configuration
information from the scanner using RIO block
transfers. If a 1746-NI4 analog input module is used
with the 1747-ASB module, a RIO block transfer is
used to transfer 1747-NI4 image data between the
scanner and the 1747-ASB module. However the
1746-NI4 module requires no configuration
information from the scanner.
In addition , the 1771-IFE image layout is not the
same as the 1746-NI4 image layout. For example,
the 1771-IFE image contains some alarm values and
has words for the module's eight inputs. The
1746-NI4 image only has words for the module's four
inputs.
If the 1747-ASB module is configured for the discrete
mode, it attempts to map all specialty I/O modules
discretely. For more information on how discrete
I/O modules are mapped, refer to page 3-13.