Rockwell Automation 1738-AENTR, Series A 1734 POINT I/O and 1738 ArmorPOINT I/O 2 Port Ethernet/IP Adapter User Manual - Manual (Page 11)

Rockwell Automation Publication 1734-UM014B-EN-P - June 2013 3
About the Adapters Chapter 1
In an attempt to address these situations, you must observe the following rules for
I/O system construction and the
removal and reinsertion of modules.
• A correct I/O system does not have any empty terminal bases.
• After you cycle power, the adapter will not allow any I/O connections
until the number of modules comprising the chassis plus one for the
adapter equals
the stored chassis size.
– It cannot assume any safe operation until there is a match between the
number of modules indicating their presence in the chassis and what the
adapter has saved in non-volatile memory because it cannot detect
empty terminal bases.
– Actual module identification (such as, electronic keying) is done when
connection establishment requests are received from the controller or
controllers.
• A POINT I/O module removed under power does not disrupt operation
of the other I/O modules. On the other hand, ArmorPOINT I/O
modules are not intended to be removed under power.
–
When you remove a module, the adapter detects what changed.
– Whenever you remove a module with an active connection from the
POINT I/O system, the adapter indicates this by flashing the
POINTBus Status LED red and reports a minor recoverable fault.
• If more than one contiguous module is removed under power, connections
to all modules in the contiguous missing module set are disallowed until all
modules are replaced. Because the adapter cannot detect an empty base, it
does not know the physical positioning of the modules until all the missing
modules are replaced.
• If a module separating two sets of contiguous missing modules is removed,
the two sets merge into a single set. All the modules must be replaced
before connections are permitted to any module in the set.
• If modules of different types are removed and returned to the wrong
locations, attempts to connect to these modules will fail during verification
of the electronic ID (providing that keying has not been disabled).
• If modules of the same type are removed and returned to the wrong
locations, they accept connections from the controller or controllers and
reconfigure with the correct data once they pass their electronic keying
check.
• These removal and return situations exist whether the system is under
power or not. If the system is under power, the situation arises immediately.
If the system is not under power, the situation arises in the next power
cycle.
Power Up a System for the First Time
When you power the I/O for the first time, the adapter must assign slot addresses
to every module in the backplane. All I/O modules ship configured at the same
address.