Redundancy Module 1756-RM2K Allen Bradley Enhanced

Product Overview

The Allen-Bradley 1756-RM2K is a conformal-coated enhanced redundancy module for ControlLogix systems. Installed in pairs across two chassis, it synchronizes controller memory and I/O data over a dual-channel fiber optic link at 1000 Mbps, enabling bumpless switchover between primary and secondary controllers.

Key Specs

• Synchronization speed: 1000 Mbps
• Max fiber distance: 10 km
• Wavelength: 1310 nm
• Current draw: 1.16 A @ 5.1 V DC, 3.4 mA @ 24 V DC
• Power dissipation: 6 W max
• Compatible controllers: ControlLogix 5560 and 5570 series
• Compatible cables: 1756-RMC1 (1 m), 1756-RMC3 (3 m), 1756-RMC10 (10 m)

Why Choose This

• Gigabit-class fiber synchronization supports chassis separation up to 10 km
• Conformal coating protects against corrosive industrial atmospheres
• Fast switchover maintains process continuity on primary controller failure
• 4-character alphanumeric display for local status monitoring

Common Questions

• Can I mix 1756-RM and 1756-RM2 modules? No, both chassis must use the same redundancy module type.
• How many modules are required? One 1756-RM2K per chassis, with two chassis total for a redundant pair.
• What fiber cable is used? 8.5/125 micron single-mode fiber with LC connectors via 1756-RMC series cables.

Mounting Steps

1. Install one module in each chassis at the same relative slot position.
2. Connect the dual-channel fiber link between the two modules.
3. Verify the 4-character display shows matching status on both modules.
4. Configure controller redundancy in Studio 5000 Logix Designer.
5. Test switchover functionality before placing the system in production.

Buying Advice

• Choose 1756-RM2K for corrosive environments; use 1756-RM2 for standard conditions.
• For extreme temperatures, select the 1756-RM2XT variant.
• Budget 1.16 A at 5.1 V DC per module in chassis power calculations.