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Mitsubishi Electric A2ACPUP21 MELSEC A Series Data Link CPU Unit

Mitsubishi Electric A2ACPUP21 MELSEC A Series Data Link CPU Unit

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  • Manufacturer: Mitsubishi Electric

  • Product No.: A2ACPUP21

  • Country of origin:United States

  • Product Type: PLC CPU Modules

  • Payment: T/T, Western Union

  • Weight: 500g

  • Dimensions: 250 mm x 110 mm x 130 mm

  • Shipping port: Xiamen

  • Warranty: 12 months

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Description

Integrating advanced optical network connectivity directly into the processor architecture, the Mitsubishi Electric A2ACPUP21 serves as a specialized central processing unit for the legacy MELSEC A Series PLC platform. This module combines the processing performance of an A2ACPU core with an integrated MELSECNET optical data link interface, providing high-speed peer-to-peer and master-sub station communications across fiber-optic loops. By consolidating control execution and optical networking capabilities onto a single slot, this CPU unit optimizes backplane space efficiency and minimizes communication latency within distributed control topologies.

Key Features

  • Integrated Optical Interface: Eliminates the need for a separate network module by building MELSECNET optical loop capabilities directly into the CPU.
  • Advanced Instruction Processing: High-speed execution of logic, sequence, and data manipulation instructions native to the A-Series controller range.
  • Noise-Immune Communication: Fiber-optic transmission path provides absolute immunity to electromagnetic interference (EMI) and radio frequency interference (RFI) in harsh environments.
  • Dual-Loop Redundancy: Supports optical loop configurations to ensure uninterrupted communications in the event of a single cable breakage.

Applications

  • Automotive assembly line synchronization over distributed networks.
  • Municipal water treatment facilities requiring isolated, long-distance inter-station communication.
  • Heavy metallurgical processing plants with high EMI/RFI electrical noise profiles.
  • Large-scale material handling and conveyor network control architectures.

Technical Specifications

Manufacturer Mitsubishi Electric
Model Number A2ACPUP21
Product Line MELSEC A Series
Module Type Data Link PLC CPU Unit
Network Interface MELSECNET Optical Fiber Loop (P21 Type)
Medium Link Connection Dual-core optical fiber cable (SI/GI spec)
Operating Temperature 0 to 55 degC
Country of Origin Japan
Shipping Weight (Calculated) 2.0 kg (4.41 lbs)
Package Dimensions (Calculated) 250 mm x 110 mm x 130 mm

Optical Connections and Interfaces

Port / Interface Function / Cable Assignment
TX Port Optical fiber transmitter (outbound loop segment)
RX Port Optical fiber receiver (inbound loop segment)
RS-232C Port Programming, debugging, and peripheral connectivity interface

Empirical Engineering Insights

Alternative Models & Compatibility

The A2ACPUP21 integrates functions equivalent to an A2ACPU combined with an AJ71LP21 optical data link card. When replacing older non-integrated configurations, ensure your program address allocations accommodate the integrated link parameters. Be aware that the optical transceiver circuits are optimized for SI-type (plastic-clad) or GI-type (glass) fiber optic cables; matching the correct cable attenuation characteristics is critical for link stability.

Application Pitfalls & Engineering Notes

A common field issue with legacy MELSECNET optical modules is signal degradation caused by micro-bends or dust accumulation inside the fiber ports. Ensure you maintain the manufacturer's specified minimum bend radius for the fiber cables inside the wiring duct. Always use standard protective dust caps on unused RX/TX channels to prevent contamination of the optical transceiver lenses.

Commissioning & Wiring Tips

During initial commissioning, verify the station number and network settings using the hardware rotary switches located on the front faceplate of the CPU prior to powering up the chassis. If the "L.ERR" (Link Error) LED activates, verify that the TX of the master station is connected directly to the RX of the local station. Interchanging the TX/RX fiber connections is the leading cause of initial handshake failures in redundant optical loop configurations.

Installation Guidelines

CRITICAL WARNING

Isolate and lock out all AC/DC power sources feeding the PLC backplane chassis before installing, removing, or adjusting the CPU unit. Failure to completely de-energize the system can result in electrical shock, hardware destruction, or erratic control system behaviors that could lead to machinery damage.

1
Ensure the main chassis base unit is securely mounted and the system power supply module is fully de-energized.
2
Align the bottom retention hook of the A2ACPUP21 CPU module with the base unit guide slot, then pivot the module firmly into the backplane connector.
3
Secure the module retention screw at the top of the unit to ensure mechanical stability against industrial vibrations.
4
Connect the dual optical fiber loops to the RX and TX ports, ensuring proper latching alignment, and secure the peripheral RS-232C programming line.

What is the primary technical advantage of using the A2ACPUP21 unit?

The module consolidates a standard MELSEC A2ACPU processor and a MELSECNET/II optical network transceiver onto a single module footprint, reducing backplane slot usage and streamlining configuration.

Which fiber-optic cable types are compatible with the integrated P21 interface?

It is designed for standard SI-type (silica glass core with plastic cladding) or GI-type (graded index glass) multi-mode optical cables, depending on the distance requirements of your network segment.

What diagnostic step should I take if the L.ERR LED lights up on commissioning?

Verify the physical fiber loop path routing. Ensure that the TX port of the upstream station is connected to the RX port of this unit, and verify that the station number switches on the front panel are set to unique values.

Global Express Shipping

  • Standard Delivery: 4-6 Business Days via DHL, FedEx, and UPS.
  • Express Dispatch: Same-day dispatch for in-stock orders placed before 2:00 PM (GMT+8).
  • Worldwide Coverage: Serving over 150 countries, including rapid delivery to Saudi Arabia and UAE.

Returns & Warranty

  • 30-Day Guarantee: Returns accepted for in-stock products in original, factory-sealed packaging.
  • 12-Month Warranty: Every industrial component is backed by our professional technical warranty.

Orders are processed and delivered Monday-Friday (excluding public holidays).


For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .

TECHNICAL SPECIFICATIONS

Country of origin
United States

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