Schneider Modicon M340 PLC Series: Specifications, Modules & Replacement Guide

1. Introduction

As a leading supplier of industrial automation spare parts, we provide a comprehensive portfolio of Schneider modicon products, specializing in original modicon plc controllers and modules.

In the fast-evolving landscape of modern industrial automation, Schneider Electric has established a robust reputation for delivering high-performance, reliable control architectures. Within this extensive ecosystem, the Modicon M340 series stands out as a core solution designed specifically for mid-range applications.

Combining compact design, high processing speed, and seamless connectivity, the M340 acts as a critical bridge for plant managers and engineers seeking optimal efficiency and system stability. Whether you are scaling up operations or maintaining existing production lines, integrating proven Modicon controllers ensures long-term operational resilience and minimized downtime.

2. Why Choose Modicon M340?

As a core mid-range platform in industrial automation, the Modicon M340 strikes an optimal balance between processing performance, communication flexibility, and long-term reliability. For engineers and technical buyers, its core value is reflected in several key dimensions:

High-Performance Processing: Powered by a 32-bit RISC core, the series handles complex automation tasks effortlessly. The flagship BMXP342020 features boolean execution speeds of 0.12 to 0.18 microseconds and floating-point processing at 1.74 microseconds. For high-precision requirements, the BMXP3420302 supports parallel processing for main, fast, and periodic event tasks.

Integrated Multi-Protocol Communication: CPUs feature three built-in ports—Ethernet (Modbus TCP and integrated web server), Serial (RS232/RS485 supporting Modbus RTU), and a Mini-B USB programming port. The BMXP3420302 manages up to 63 Ethernet slaves and 63 CANopen slaves, while the BMXNOM0200 module further extends serial connectivity for third-party instruments and barcode scanners.

Modular Expansion Architecture: The system supports up to 4 racks with 11 slots per rack, scaling up to 1,024 discrete I/O points and 256 analog I/O points to fit diverse application scales.

Comprehensive I/O Ecosystem: A full range of digital, analog, high-speed counting, and motion control modules ensures complete application coverage.

Industrial-Grade Reliability: Built with robust components featuring high electromagnetic immunity and a standard operating temperature range of 0°C to 60°C.

Investment Protection: Serving as an ideal upgrade path for legacy TSX systems, the platform utilizes EcoStruxure Control Expert (Unity Pro) software, supporting all IEC 61131-3 programming languages with online diagnostics and hot-swapping capabilities.

3. Core Modules & Accessories

Whether you are maintaining legacy setups or upgrading your current modicon plcs, having access to reliable modicon plcs & accessories—such as communication modules, power supplies, and racks—is critical for system stability.

As a core mid-range automation platform, the Modicon M340 series is widely applied in discrete manufacturing, water treatment, packaging, and energy systems due to its balanced performance, flexible architecture, and comprehensive communication interfaces. Below is an inventory breakdown of the core modules and accessories:

I. CPU Processor Modules

The series provides multiple CPUs matching diverse control demands, all programmed via EcoStruxure Control Expert (Unity Pro):

BMXP342020: Features a 32-bit RISC core with 3584 KB user memory (4096 KB total RAM), boolean execution at 0.12–0.18 µs, standard 8MB SD card, and integrated Ethernet, serial, and USB ports. Ideal for mid-scale machine automation and production line coordination.

BMXP3420302: High-performance variant supporting up to 63 CANopen slaves, 63 Ethernet slaves, 36 dedicated channels, and advanced motion control.

BMXP3420102: Features 256 KB memory, supporting up to 4 racks and 11 slots with IP20 protection, tailored for packaging, textiles, and material handling.

BMXP341000: Dedicated high-performance processing module for specialized communication or high-speed counting tasks.

BMXP342000: Provides 1792 KB programming capacity supporting 1024 discrete I/O points, 256 analog points, 36 counter channels, and 3 communication ports.

II. Power Supply Modules

Power supplies deliver stable backplane and I/O power, selected based on system load and redundancy requirements:

BMXCPS2000: Standard AC model (85–264V AC input) delivering 24V DC / 3.3V DC with a total power output of 20W plus overload, overvoltage, and short-circuit protection.

BMXCPS3020 / BMXCPS3500: Higher-power and heavy-duty configurations designed for systems with dense I/O requirements.

BMXCPS4002/4022: High-performance dual-power redundant supplies ensuring zero-downtime operation for critical applications.

III. I/O Modules

The M340 ecosystem includes hot-swappable I/O options covering digital, analog, and motion requirements:

Digital Modules: Includes the 16-input BMXDDI1602, 32-input BMXDDI3202K, 64-input BMXDDI6402K, 32-output BMXDDO3202K, and 64-output BMXDDO6402K.

Analog Modules: Features the 8-channel universal input BMXAMI0810 (supporting current, voltage, RTD, and thermocouple with 16-bit resolution and channel isolation), hybrid 4-input/2-output BMXAMM0600 (1 ms/channel sampling), and analog outputs like BMXAMO0210H and BMXAMO0410.

Motion & Counting: BMXEHC0200 high-speed counter module, paired with the BMXXTSHSC20 connector kit (comprising one 10-pin and two 16-pin spring terminal blocks).

IV. Communication Modules

BMXNOE0100: Ethernet module supporting Modbus TCP for HMI and SCADA integration.

BMXNOM0200: Serial communication module featuring 2 RJ45 ports (1x RS232, 1x RS485), supporting Modbus RTU/ASCII master-slave with 500Vrms isolation.

BMXNOC0401: CANopen networking module for distributed device connectivity.

BMXPRA0100: Remote I/O adapter supporting hot-swapping and a built-in real-time clock for distributed architectures.

V. Racks and Critical Accessories

Backplanes (Racks): Available in 4-slot (BMXXBP0400), 6-slot (BMXXBP0600), 8-slot (BMXXBP0800), and 12-slot (BMXXBP1200) variations.

System Accessories:

BMXRMS008MP: 8MB SD memory card for user program backup and non-volatile data storage.

Terminal Blocks: Spring-clamp terminal blocks like BMXFTB2820 (28-pin, tool-free wiring, vibration-resistant) alongside BMXFTB2010 and BMXFTB2800 variants designed to minimize maintenance downtime.

VI. Maintenance Value of Accessories

While minor in footprint, accessories govern long-term operational stability 

Storage Cards: Programs reside on standard SD media, automatically mirroring data to internal Flash upon power-down without requiring batteries, ensuring seamless "plug-and-play" deployment.

Terminal Blocks: Spring-loaded designs (e.g., BMXFTB2820) accelerate field wiring while maintaining robust clamping force under heavy vibration typical of pumps, fans, and production lines, permitting module swaps without rewiring.

Redundancy & Adapters: Remote adapters allow live insertion/removal, and power redundancy schemes switch over within 10 milliseconds to isolate faults without halting primary production.

Senior Engineer's Hands-On Troubleshooting Guide

When integrating the Modicon M340 series into real-world industrial environments, avoiding common system design pitfalls ensures long-term operational stability.

1. The Compatibility Trap

• The Risk: In discrete manufacturing and water treatment projects, mixing multi-generation racks within a single architecture often leads to intermittent communication instability if you rely solely on surface-level datasheet specs.

• The Solution: Always evaluate environmental load profiles alongside rack power distribution constraints during the initial design phase.

2. Real-World Case Insight

• The Challenge: A major municipal water plant experienced frequent packet loss and communication dropouts caused by severe electromagnetic interference (EMI).

• Our Approach: Our technical team resolved the issue by meticulously adjusting the backplane bus configuration and optimizing the physical module layout within the enclosure.

3. Expert Technical Support

• Need Assistance? If you encounter complex integration challenges or are planning an active legacy system upgrade, share your system architecture diagram with us. Our engineering team provides professional, hands-on optimization advice to ensure seamless compatibility.

4. Applications & Legacy Upgrades

I. Typical Application Scenarios

Water Treatment & Environmental Protection: The M340 series is widely deployed in wastewater facilities. For instance, in a steel group's integrated sewage treatment plant, M340 controllers manage lower-tier processes across a ring network of switches, handling screen rooms and lift pumping stations. Built-in PID function blocks execute constant-flow control, while analog modules like the BMXAMI0810 collect critical telemetry such as temperature, pressure, flow, and level.

Packaging & Machinery Manufacturing: Combining compact modular architecture with high processing speeds (0.12–0.18 µs boolean execution), CPUs like the BMXP342020 manage up to 1,024 discrete and 256 analog points for medium-scale lines. The hybrid BMXAMM0600 module provides 4 inputs and 2 outputs with a 1 ms/channel sampling rate, suiting high-dynamic systems like packaging and tension control.

Infrastructure & Energy: Supporting up to 4 racks and remote I/O adapters like the BMXPRA0100, the platform facilitates distributed control across tunnels, transit, and energy projects. Native Modbus TCP Ethernet integration simplifies SCADA connectivity for sorting and distribution systems.

II. Legacy System Upgrade Pathways

Replacing TSX Series: M340 serves as the primary modernization path for aging TSX platforms, delivering major performance gains, native Ethernet/USB/serial ports, and an 8MB SD card standard while utilizing EcoStruxure Control Expert (Unity Pro) for streamlined code migration.

Smooth Modular Transition: Upgrades can proceed in stages—swapping the core CPU (e.g., BMXP3420302) first before replacing legacy I/O lines. Utilizing X80 shared infrastructure components such as BMXCPS2000 power units and BMXNOM0200 serial modules alongside hot-swappable backplanes (BMXXBP0400–1200) and terminal blocks (BMXFTB2820) minimizes downtime during cutovers.

III. Upgrading Considerations

Before migration, evaluate total I/O requirements, network protocols, and logic complexity. The platform natively supports Modbus RTU/TCP and CANopen to preserve field device compatibility. Specialized components like high-speed counters (BMXEHC0200) require hardware configuration verification within Unity Pro prior to deployment.

5. In-Stock Availability & Get a Quote

When dealing with critical industrial automation systems, minimizing downtime is everything. That is why we maintain a robust, ready-to-ship inventory of genuine Schneider Modicon M340 components. Whether you are looking to replace a faulty CPU, expand your I/O capacity, or secure reliable backup modules for your facility, we ensure a seamless procurement experience.

100% Original & Brand New: Every controller, processor, and accessory we supply is authentic and sourced through verified channels.

Global Express Shipping: We understand the urgency of industrial maintenance and ship our parts worldwide to get your operations back on track quickly.

12-Month Warranty: Shop with confidence knowing our comprehensive quality assurance fully backs your investment.

Ready to secure your hardware? Submit your required part numbers, and our technical sales team will provide an immediate response with pricing and availability.

Back to the top: Modicon PLC