Allen-Bradley ControlNet PLC-5 User Manual page 52

2-12 Planning to Use Your ControlNet PLC-5 Processor
1785-UM022B-EN-P - February 2002
There are four general types of scheduled connections from the
ControlNet PLC-5 to I/O adapters:
• exclusive owner - these scheduled connections indicate the
PLC-5 has exclusive ownership of the outputs. These scheduled
connections can also gather inputs from the device. There cannot
be more than one exclusive owner connection made to either the
rack connection or module connection at a time.
• input only - these scheduled connections only gather inputs from
the I/O adapters. These scheduled connections do not require
other scheduled connection types to be first established before its
scheduled connection can be established.
• listen only - these scheduled connections are similar to input only
scheduled connections, except that they require a different
scheduled connection to be first established before its connection
can be established.
• redundant owner - these scheduled connections are similar to
exclusive owner scheduled connections because they both can
control outputs and gather inputs. The difference between them is
that with redundant owner scheduled connections, multiple
ControlNet PLC-5 controllers can establish identical redundant
connections. Only one of the controllers that establish the
redundant scheduled connection will own the outputs.
Redundant connections can only be used in a PLC-5 ControlNet
Hot Backup system. Refer to the PLC-5 ControlNet Hot Backup
User Manual, publication 1785-6.5.24 for more information on
using redundant connections.
Allowable Scheduled Connection Type Combinations for I/O
Adapter Connections
Only specific combinations of scheduled connection types are
allowable. RSNetWorx will have a pull down list showing all
allowable schedule connection types.
The following details about these combinations assume that different
processors are making either rack connections to the same adapter or
module connections to the same slot.
Important: The 1771-ACN(R15) requires a rack connection to be
established before any module connections are accepted.
If an exclusive owner connection is made to the adapter:
• another exclusive owner connection will be rejected
• an input only connection can be made
• a listen only connection can be made
• a redundant owner connection will be rejected