Honeywell 900RSM-0101 Redundant Switch Module (RSM)

Product Overview

The Honeywell 900RSM-0101 is a Redundant Switch Module (RSM) designed for the ControlEdge HC900 redundant controller rack. It manages seamless failover between the Lead and Reserve CPUs, providing real-time status indication, manual switchover capability, and key-switch mode control. The 900RSM-0101 ensures high availability in critical process control and safety applications by eliminating single points of failure in the controller architecture. It supports Insertion/Removal Under Power (IRUP) without inducing a controller failover.

Key Features

• Redundancy management between Lead and Reserve CPUs
• Lead/Reserve LED indicators for instant CPU status visibility
• Manual failover key switch — force switchover from Lead to Reserve
• Mode selection key switch: RUN, PROGRAM, RUN/PROG
• Hot-swappable (IRUP) — may be replaced under power without inducing failover
• C70R CPUs remain in last used mode during RSM replacement
• One RSM required per redundant controller rack
• Class 1, Division 2, Groups A,B,C,D, T6 hazardous location rating

Technical Specifications

• Model: 900RSM-0101
• Product Type: Redundant Switch Module (RSM)
• Series: ControlEdge HC900
• Function: Redundancy management, manual failover, mode control
• CPU Compatibility: C70R, C75 redundant CPUs
• Indicators: Lead/Reserve status LEDs
• Key Switches: Mode (RUN / PROGRAM / RUN/PROG) + Manual failover
• Hot-Swap Support: IRUP — insertion/removal under power supported
• Failover Behavior: Replacement does not induce controller failover
• Rack Requirement: One per redundant controller rack
• Operating Temperature: 0°C to +60°C
• Storage Temperature: −25°C to +70°C
• Humidity: 5% to 95% RH (non-condensing)
• Weight: Approx. 0.5 kg (500 g)
• Dimensions: Standard HC900 module form factor
• Hazardous Location: Class 1, Div 2, Groups A,B,C,D, T6
• Certifications: CE, UL, CSA, TÜV

Typical Applications

• Redundant controller architectures for high-availability process control
• Safety instrumented systems (SIS) requiring no single point of failure
• Critical batch and continuous process automation
• Oil & gas production and refining
• Power generation and turbine control

FAQ

Installation Guide

1. Power Planning: The RSM can be inserted or removed under power, but follow your plant's safety procedures.
2. Slot Placement: Install the 900RSM-0101 in the designated RSM slot in the redundant controller rack, typically positioned between the two CPUs.
3. Key Switch Setup: Set the mode key switch to the desired operating mode (RUN, PROGRAM, or RUN/PROG) before or during commissioning.
4. Failover Test: During commissioning, test manual failover using the key switch to verify Reserve CPU assumes control correctly.
5. Status Verification: Confirm Lead/Reserve LEDs indicate the correct active and standby CPUs.
6. Replacement Procedure: If replacing the RSM, simply remove the old module and insert the new one. The CPUs will maintain their last mode and control will not transfer.

Selection Tips

• Select the 900RSM-0101 for newer HC900 redundant controller racks (check your rack part number compatibility).
• For legacy redundant racks, verify whether the 900RSM-0001 or 900RSM-0200 is required instead.
• Ensure your CPU firmware supports the RSM revision before installation.
• Always pair with a redundant CPU rack (900RR0-xxxx) and dual redundant CPUs (C70R/C75).
• Plan operator training on the manual failover key switch for emergency procedures.