Honeywell 2MLR Series Modules - 2MLR-AC23-CC

Technical Dossier

Product Details And Specifications

Honeywell 2MLR Series Technical Notes

The Honeywell 2MLR series represents a core power supply and module family within the Honeywell TDC 3000, PlantScape, and Experion HS distributed control system (DCS) platforms. These systems are installed across global heavy industry sectors including petrochemical refineries, nuclear power facilities, offshore platforms, and large-scale chemical processing plants. The 2MLR designation identifies modules engineered for the High-Performance Process Manager (HPM) and related controller cabinets, where power integrity and backplane compatibility are non-negotiable operational requirements. Installed base counts for TDC 3000 and its successor platforms number in the tens of thousands of cabinets worldwide, making the 2MLR series one of the most persistently demanded spare part families in the industrial automation aftermarket.

The Evolution of 2MLR Architecture

The 2MLR module family was introduced as part of Honeywell's second-generation TDC 3000 cabinet infrastructure, designed to replace earlier single-rail power architectures with redundant, hot-swappable power distribution. Early variants such as the 2MLR-AC23-CC established the AC input / DC output conversion standard used across HPM and IOP (Input/Output Processor) enclosures. As the platform evolved through the PlantScape and Experion HS generations, the 2MLR series maintained backward-compatible backplane pinouts, allowing legacy cabinets to accept updated module revisions without full cabinet replacement. This architectural continuity is a primary reason why 2MLR modules remain in active service in plants with 20–30 year operational horizons. Compatibility constraints center on firmware revision matching between power modules and their associated controller cards, as well as physical slot keying that differs between HPM, APM (Advanced Process Manager), and LCN (Local Control Network) enclosure types. Procurement teams must verify the exact revision suffix (e.g., -CC, -CA, -CB) to ensure drop-in replacement without reconfiguration.

2MLR Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly sourced models within the Honeywell 2MLR series. Each entry reflects a distinct functional role within the TDC 3000 / Experion HS cabinet architecture.

2MLR-AC23-CC: AC input power supply module, 120/240 VAC to 24 VDC, HPM cabinet primary rail.
2MLR-AC23-CA: Earlier revision of AC23 power supply; functionally equivalent, revision-A firmware baseline.
2MLR-AC23-CB: Intermediate revision with enhanced thermal protection circuitry for high-ambient installations.
2MLR-DC23-CC: DC input variant, 24–48 VDC input range, for battery-backed or DC-bus cabinet configurations.
2MLR-DC23-CA: First-release DC input power module; used in early HPM redundant power configurations.
2MLR-PS01: Auxiliary power supply card for IOP (Input/Output Processor) sub-enclosures.
2MLR-PS02: Upgraded IOP power card with improved ripple suppression for analog I/O accuracy.
2MLR-PS03: High-current IOP power module supporting expanded I/O card counts per enclosure.
2MLR-RPLY: Power relay and distribution module; manages load switching between redundant power rails.
2MLR-FUSE: Fused power distribution card; provides per-slot overcurrent protection within HPM backplane.
2MLR-BKPL: Backplane interface module; bridges power bus between primary and secondary cabinet sections.
2MLR-CHRG: Battery charger module for UPS-integrated HPM cabinet configurations.
2MLR-MON: Power monitoring and diagnostics module; reports rail voltage and current to the Universal Station.
2MLR-XFMR: Internal transformer isolation module for noise-sensitive analog process control loops.
2MLR-REDUN: Redundancy switchover module; enables bumpless transfer between primary and backup power supplies.