User manual

Rockwell Automation Publication 1756-UM001O-EN-P - October 2014 179
Redundant Systems Chapter 12
Enhanced Versus Standard Redundancy
While the enhanced and standard redundancy systems operate in a similar
manner, there are some key differences between the two platforms. Ta b l e 4 7
compares the enhanced and standard redundancy system features.
Build a Redundant System
To build a typical redundant system, perform this procedure.
1. Install a ControlLogix chassis and power supply.
2. To the primary chassis, add 1756-L6x or 1756-L7x controllers.
You cannot mix 1756-L6x and 1756-L7x controllers in the same chassis.
3. Add one or more ControlNet or EtherNet/IP communication modules.
4. Add one redundancy module.
5. Configure a secondary chassis that is identical to the primary chassis.
6. Connect the redundancy modules in the chassis.
7. Add I/O modules to ControlNet or EtherNet/IP networks.
8. Add operator interfaces to ControlNet or EtherNet/IP networks.
For detailed information to design and build an enhanced redundant system, see
the ControlLogix Enhanced Redundancy System User Manual, publication
1756-UM535
.
Table 47 - Comparison of Enhanced Redundancy to Standard Redundancy
Feature Enhanced
System
(1)
(1) Availability of some features that are supported in enhanced redundancy is dependent on the system revision used. For more
information, see ControlLogix Enhanced Redundancy System User Manual, publication 1756-UM535
.
Standard
System
Supports enhanced ControlLogix ControlNet and EtherNet/IP communication
modules, for example, the 1756-CN2/B or 1756-EN2T modules

Supports standard ControlLogix ControlNet and EtherNet/IP communication
modules, for example, the 1756-CNB/D or 1756-ENBT modules

Compatible with the single-slot 1756-RM redundancy modules

Compatible with the double-slot 1757-SRM redundancy modules

Support for all 1756-L6x and 1756-L7x ControlLogix controllers

Use of ControlLogix- system components, for example, the 1756-L63XT controller
and the 1756-CN2XT module

Availability of I/O over an EtherNet/IP network, including Redundant I/O systems

IMPORTANT
Components in the redundant chassis pair must be identical in
module configuration.