Mitsubishi A3NCPUR21 CPU Module – MELSEC-A Series Programmable Logic Controller Processor Unit
When a CPU module fails on the production floor, everything stops. Conveyor lines freeze, robotic arms halt mid-cycle, and every minute of unplanned downtime translates directly into lost revenue and missed delivery commitments. In legacy MELSEC-A Series installations — still running reliably in automotive plants, food processing facilities, and utility infrastructure worldwide — finding a verified replacement CPU is not a luxury; it is the difference between a two-hour recovery and a two-week shutdown. The Mitsubishi A3NCPUR21 CPU Module is that critical replacement part.
The A3NCPUR21 occupies a well-defined position within the MELSEC-A Series architecture. As a high-performance CPU unit designed for the A3N base unit, it delivers the processing throughput and program capacity required by complex, multi-axis control applications. The MELSEC-A Series has been a cornerstone of global industrial automation since its introduction, and Mitsubishi Electric’s commitment to long-lifecycle support has kept these controllers operational in mission-critical environments for decades. Sourcing a genuine A3NCPUR21 ensures full backward compatibility with existing ladder logic programs, I/O configurations, and peripheral devices — protecting your engineering investment without requiring a costly system migration.
Technical Specifications
- Part Number / SKU: A3NCPUR21
- Manufacturer: Mitsubishi Electric
- Series: MELSEC-A Series
- Module Type: CPU (Central Processing Unit) Module
- Compatible Base Unit: A3N Series base units
- Programming Language: Ladder Diagram (LD), compatible with GX Developer / GX Works
- Communication Interface: RS-232C programming port (standard)
- Operating Temperature: 0°C to 55°C
- Storage Temperature: -20°C to 75°C
- Power Consumption: Refer to official Mitsubishi Electric datasheet
- Weight: Approx. 2,500 g (module with packaging)
- Compliance: CE, UL (verify current certification status with datasheet)
Note: All specifications are sourced from publicly available Mitsubishi Electric documentation. Konmask.com does not fabricate or modify manufacturer specifications. Always verify against the official product datasheet before engineering decisions.
Key Features & Benefits
- Drop-in Replacement Compatibility: Designed as a direct replacement for existing A3NCPUR21 units in MELSEC-A Series systems — no rewiring, no reprogramming of the base architecture.
- High Processing Performance: Delivers the scan-time performance required for demanding, multi-device control loops in continuous manufacturing environments.
- Program Retention: Battery-backed RAM preserves user programs and data during power interruptions, minimizing recovery time after outages.
- Robust Industrial Design: Built to Mitsubishi Electric’s industrial-grade standards for vibration, humidity, and electromagnetic interference resistance.
- Long Lifecycle Support: MELSEC-A Series components remain available through specialist distributors like Konmask.com, extending the operational life of installed systems.
- GX Developer Compatible: Fully programmable and diagnosable using Mitsubishi’s standard GX Developer and GX Works software toolchain.
Industry & Equipment Applications
- Automotive Manufacturing: Body welding lines, paint shop conveyors, and assembly robot controllers using legacy MELSEC-A platforms.
- Food & Beverage Processing: Bottling lines, packaging machines, and batch processing systems requiring continuous, reliable CPU operation.
- Utilities & Water Treatment: Pump station control, SCADA-integrated PLC nodes, and substation automation panels.
- Textile & Printing Machinery: Multi-axis tension control and register control systems built on MELSEC-A architecture.
- Material Handling: Warehouse conveyor systems, sortation equipment, and automated storage and retrieval systems (AS/RS).
- Chemical & Petrochemical Plants: Process control loops where system migration is cost-prohibitive and legacy CPU continuity is mandatory.
System Integration & Compatible Parts
The A3NCPUR21 is designed to operate within the broader MELSEC-A Series ecosystem. Compatible and commonly paired components include:
- Base Units: A3N, A3A, A2N series base units
- Power Supply Modules: A61P, A62P, A63P series
- I/O Modules: AX40, AX80, AY40, AY80 series digital I/O; AD series analog I/O
- Communication Modules: A1SJ71UC24-R2, A1SJ71E71-B2 for network connectivity
- Programming Cables: SC-09, USB-SC09-FX (with adapter) for GX Developer connection
- Memory Cassettes: A3NMCA-8, A3NMCA-16 for extended program storage
Contact our technical team to confirm compatibility with your specific system configuration before ordering.
Our Quality Assurance Process
At Konmask.com, every industrial automation component goes through a structured sourcing and verification process before it reaches our customers:
- Authorized Supply Chain: We source from verified distributors and original equipment channels to minimize counterfeit risk.
- Visual & Functional Inspection: Each unit is inspected for physical integrity, label authenticity, and connector condition.
- Traceability Documentation: We maintain sourcing records for every batch, available upon request for regulated industries.
- Secure Packaging: Anti-static packaging with moisture barrier protection for safe international shipping.
- Post-Sale Support: Our engineering team is available to assist with installation questions and compatibility verification.
How to Order
- Submit an Inquiry: Use the contact form or email [email protected] with your required quantity and delivery timeline.
- Receive a Quote: Our team will respond within 1 business day with pricing, availability, and lead time.
- Confirm & Pay: Approve the proforma invoice and complete payment via your preferred method (T/T, PayPal, or other agreed terms).
- Shipment & Tracking: We ship via DHL, FedEx, or UPS with full tracking. Export documentation provided for international orders.
- After-Sales Support: Contact us anytime post-delivery for technical assistance or warranty claims.
Why Choose Konmask.com?
- ✅ Specialist in industrial automation components — PLC, DCS, servo, HMI, and drives
- ✅ Global B2B supply with export documentation for 50+ countries
- ✅ Fast response: inquiries answered within 24 hours
- ✅ Technical expertise: our team understands the products we sell
- ✅ Competitive pricing on hard-to-find legacy and current-generation parts
- ✅ Secure, traceable supply chain with anti-counterfeit measures
Frequently Asked Questions
- Q: Is the A3NCPUR21 still in production by Mitsubishi Electric?
- A: The MELSEC-A Series has reached end-of-life status with the manufacturer. However, genuine units remain available through specialist distributors. Contact us to check current stock availability.
- Q: Can I use the A3NCPUR21 with GX Works2 or GX Works3?
- A: The A3NCPUR21 is primarily supported by GX Developer. Limited compatibility may exist with GX Works2 in A-Series mode. We recommend confirming with your software version before programming.
- Q: Do you provide a warranty on this module?
- A: Yes. We offer a standard warranty period on all modules. Please contact us for specific warranty terms applicable to your order.
- Q: Can you supply multiple units for a plant-wide spare parts program?
- A: Absolutely. We regularly supply bulk orders for MRO and spare parts programs. Contact us with your quantity requirements for volume pricing.
- Q: What shipping options are available for international orders?
- A: We ship worldwide via DHL Express, FedEx International Priority, and UPS Worldwide. All shipments include tracking and commercial invoice documentation.
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