Adapter Replacement; Empty Slots And Riup Situations - Allen-Bradley Rockwell Automation 1734-AENT User Manual

2 About the Adapter
Publication 1734-UM011D-EN-P - May 2011
The default setting for the chassis size is 1 slot, which represents the adapter
by itself.
Set the chassis size as the sum of the slot of the adapter plus the slots of each
I/O module in the adapter backplane. For example, the adapter plus 4 I/O
modules uses a chassis size of 5. The adapter stores this chassis size setting in
non-volatile storage.
When the adapter's non-volatile chassis size does not match the actual number
of modules present on its backplane, the adapter does not make any I/O
connections and an error occurs, as shown in the Module Properties dialog.

Adapter Replacement

It is important to note that during a connection request from the controller,
the chassis size setting for a 1734-AENT adapter is not communicated to the
adapter. You must always set this chassis size using a separate operation. This
includes situations when you are replacing an adapter. The adapter does not
make any I/O connections until it is configured with the appropriate chassis
size.

Empty Slots and RIUP Situations

The POINT I/O system does not have the ability to detect an empty terminal
base. Because of this, there are numerous situations in which you can
potentially configure a system that is unusable or one that exercises unintended
control.
In an attempt to address these situations, you must observe the following rules
for POINT I/O system construction and the removal and reinsertion of
modules: