Honeywell 2MLB-M12A 12-Slot Main CPU Baseplate

Product Overview

The Honeywell 2MLB-M12A is a 12-slot main CPU baseplate for the MasterLogic-200 (ML200) non-redundant PLC system. It provides the mechanical and electrical foundation for installing the 2MLI-CPUU CPU module, I/O modules, communication modules, and power supplies. With integrated backplane bus communication and power distribution, it enables centralized, high-density control architectures in a compact 19 mm depth design.

Key Specifications

• Product Type: 12-Slot Main CPU Baseplate
• Series: MasterLogic-200 / ML200 (Non-Redundant)
• Slot Capacity: 12 module slots
• Compatible CPU: 2MLI-CPUU (non-redundant only)
• Power Distribution: Integrated 5V DC backplane power
• Communication Support: Backplane bus for MasterLogic-200 modules
• Expansion Support: Compatible with 2MLB-ExxA expansion bases via ribbon cable
• Dimensions (W x H x D): 426 mm x 98 mm x 19 mm
• Weight: Approx. 0.54 kg (540 g)
• Mounting: Panel or DIN rail (35 mm)
• Operating Temperature: -20°C to +60°C
• Storage Temperature: -25°C to +70°C
• Certifications: CE, RoHS

Features & Benefits

• 12-slot high capacity — supports up to 12 modules including CPU, power supply, I/O, and communication in a single rack, reducing cabinet count in large systems
• Integrated power distribution — built-in 5V DC backplane power eliminates separate power bus wiring, reducing installation time by 30%
• Ultra-slim 19 mm depth — shallow profile minimizes control cabinet depth requirements, saving valuable floor space in crowded MCC rooms
• CPU-centric design — dedicated CPU slot ensures proper backplane addressing and communication timing for the 2MLI-CPUU
• Expansion-ready — built-in expansion port connects to 2MLB-ExxA expansion bases via ribbon cable for systems exceeding 12 modules

Typical Applications

• Centralized machine control for packaging and assembly lines
• Process control skids in chemical and pharmaceutical plants
• Building automation central plant controllers
• Water treatment plant local control units
• Power plant auxiliary system control
• Any application requiring 8–12 I/O modules in a single rack

Installation Guide

1. Mount on DIN rail or panel — secure the 2MLB-M12A to a standard 35 mm DIN rail or bolt it to a panel using the integrated mounting feet.
2. Install CPU module — mount the 2MLI-CPUU in the leftmost dedicated CPU slot. Ensure it clicks firmly into place.
3. Install power supply — mount the 2MLP-ACF2 or 2MLP-DC42 in the power supply slot adjacent to the CPU.
4. Install I/O and communication modules — snap up to 10 additional modules into the remaining slots. Ensure each module clicks into place.
5. Install dummy modules in empty slots — use 2MLT-DMMA blank modules to cover unused slots and maintain environmental protection.
6. Connect expansion cable (if needed) — if using expansion bases, connect the 2MLC-Exxx ribbon cable from the expansion port to the first expansion base.

FAQ

Q: What is the difference between 2MLB-M12A and 2MLB-M08A?
A: The 2MLB-M12A has 12 module slots. The 2MLB-M08A has 8 module slots. Both are main CPU bases for non-redundant ML200 systems. Choose M12A for large I/O counts; choose M08A for compact installations.

Q: What is the difference between 2MLB-M12A and 2MLR-M06P?
A: The 2MLB-M12A is a non-redundant main base for standard ML200 systems. The 2MLR-M06P is a redundant main base for ML200R systems with dual CPU and dual power supply slots. They are not interchangeable.

Q: Can I use redundant CPUs in this base?
A: No. The 2MLB-M12A is designed exclusively for non-redundant CPUs (2MLI-CPUU, 2MLI-CPUS). Redundant CPUs (2MLR-CPUH/F, 2MLR-CPUH/T) require the ML200R redundant base (2MLR-M02P or 2MLR-M06P).

Q: What is the maximum I/O capacity with one 2MLB-M12A?
A: With 12 slots and high-density 32-point I/O modules, a single 2MLB-M12A can support up to 384 digital I/O points. With expansion bases, the 2MLI-CPUU supports up to 6,144 total I/O points.

Selection Tips

• Select 2MLB-M12A when you need 12 slots for CPU, power, I/O, and communication modules in a non-redundant system.
• For smaller systems (≤8 modules), choose 2MLB-M08A or 2MLB-M06A to reduce cost and footprint.
• Verify your CPU model — only non-redundant CPUs (2MLI-CPUU, 2MLI-CPUS) are compatible with 2MLB-M12A.
• Calculate your total module width — 12 modules at 27.4 mm each = 328.8 mm; ensure your cabinet has adequate DIN rail length.
• Always order 2MLT-DMMA dummy modules for empty slots to maintain backplane protection and thermal management.