Rockwell Automation 1756-IH16ISOE ControlLogix Sequence of Events Module - Manual (Page 132)

Publication 1756-UM528A-EN-P - April 2004
C-4 Synchronizing CSTs Across Multiple Chassis
Synchronizing Chassis in
ControlLogix Redundancy
Systems When Sequence of Events modules are used in ControlLogix
Redundancy systems, the chassis that contain the Sequence of
Events modules must be synchronized.
Figure C.3 on page C-5 shows an example ControlLogix redundancy
system that uses Sequence of Events modules in some of its remote
chassis to timestamp input transitions and 1756-SYNCH modules to
synchronize CSTs among those remote chassis.
When synchronizing time in ControlLogix redundancy systems that
also use Sequence of Events modules, remember the following:
• A time master (either ControlLogix controller or 1756-SYNCH
module) must reside in each synchronized chassis.
• All chassis containing Sequence of Events modules must also
contain 1756-SYNCH modules that provide a common CST via
SynchLink.
IMPORTANT
At the time of this printing (April 2004),
ControlLogix Redundancy was only available with
ControlLogix controllers version 11.71. To
synchronize remote Sequence of Events modules,
you must either:
• Use version 13 redundancy across the system
or
• Use version 11.71 for the redundancy
controllers and include a ControlLogix
controller, version 13, in one of the
synchronized remote chassis, as shown in the
example.
In this case, you must use two RSLogix 5000
projects–one for the redundancy controllers
(programmed with RSLogix 5000, version 11)
and one for the remote chassis controller
(programmed with RSLogix 5000, version 13).