Purchase now: Allen-Bradley 1756-RM2 Enhanced Redundancy Module
Atlantechdrives provides you the 1756-RM2, the latest generation redundancy module for the ControlLogix 1756 platform. Designed for high-speed synchronization between Primary and Secondary chassis, the 1756-RM2 offers significantly faster data transfer rates and improved diagnostics compared to the original RM module. It is the definitive choice for modernizing high-availability systems using L7 and L8 processors.
- Speed: 1000 Mbps High-Speed Fiber Link
- Distance: Supports up to 10km (with specialized SFP modules)
- Diagnostic Display: 4-character scrolling LED
- Hot-Swappable: Can be replaced without stopping the process
- Connectivity: Dual fiber ports for enhanced link redundancy
Advanced Synchronization: The 1756-RM2 Advantage
The 1756-RM2 is engineered to handle the massive data volumes of modern industrial networks. With the rise of high-density I/O and complex motion control, the synchronization link between redundant racks must be faster than ever. The 1756-RM2 provides the necessary bandwidth to ensure that even the largest tag databases are mirrored in the secondary rack in real-time. It also features enhanced «Cross-Loading» capabilities, which speed up the initial synchronization process after a chassis has been serviced. This module is essential for applications where even a 50ms delay in switchover could lead to a safety violation or a significant loss of production quality in high-speed manufacturing.
Installation Advice: SFP Modules and Link Selection
A key advantage of the 1756-RM2 is its support for Small Form-factor Pluggable (SFP) transceivers. When installing the 1756-RM2, ensure you are using the correct 1756-RMC fiber cable and that the SFPs are fully locked into the ports. For standard installations (under 10 meters), the standard SFPs are sufficient; however, for campus-wide redundancy where the primary and secondary racks are in different buildings, you may need long-distance SFPs. Always use the «Redundancy Module Tool» (RMT) to verify that both 1756-RM2 modules are at identical firmware revisions before attempting to commission the redundant pair.
Maintenance and Predictive Diagnostics
The 1756-RM2 includes a powerful internal logging system that tracks every event, switchover, and synchronization error. Maintenance teams should audit these logs monthly to identify «flapping» communication links or failing processors. The scrolling display on the front provides a «Redundancy State» at a glance—ensure the system shows «PRIM» and «STBY» (Standby) for a healthy pair. Because the 1756-RM2 handles more data and operates at higher speeds, ensure the ControlLogix chassis has optimal cooling. If the module temperature exceeds its rating, the 1756-RM2 may «disqualify» the secondary rack as a safety measure, leaving your system unprotected.
FAQs
Q: What is the difference between 1756-RM and 1756-RM2?
A: The RM2 offers faster synchronization, supports longer distances via SFPs, and provides more advanced diagnostic data.
Q: Can the 1756-RM2 be used with EtherNet/IP?
A: Yes, it is the standard module for managing redundancy in EtherNet/IP based architectures for L7 and L8 controllers.
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The enhanced 1756-RM2 module provides faster switchover speeds for critical control systems based on the ControlLogix 5573 processor.
