When a Legacy Line Goes Down, Every Hour Counts
A midstream compressor station runs its process on a Modicon M340 rack. One morning the Level 1 CPU stops responding and the whole line halts. The replacement has been discontinued since 2020, and the plant needs a working module, not a redesign. That is exactly the gap the Schneider BMXP341000 fills.
What the BMXP341000 Actually Is
This is a Modicon M340 standard CPU module, Level 1, from Schneider Electric. An ARM9 processor runs at 110 MHz, with 1792 KB of program memory for application, symbols and comments, plus 128 KB of data memory and 2048 KB total internal RAM. Program it with EcoStruxure Machine Expert (Unity Pro).
Scan performance reaches 5.4 Kinst/ms for 100% boolean logic and 4.2 Kinst/ms for mixed instructions, so typical machine and process logic executes without hesitation.
Key Specifications at a Glance
Processing and Memory
The ARM9 core and 110 MHz clock give the module predictable cycle times. The 1792 KB program memory suits applications with substantial symbol tables and commented code, which matters when a maintenance team inherits a program years later.
I/O Capacity
The CPU supports up to 512 discrete I/O points and 128 analog points across X80 racks in 4, 6, 8 or 12-slot sizes. It manages one main local rack and one expansion rack, a practical footprint for compact process skids.
Communication
Two built-in ports cover day-to-day needs: one Modbus Serial RJ45 port (RS232/RS485, non-isolated) and one USB Mini-B port. Protocols include Modbus Serial RTU/ASCII and character mode. Optional X80 communication modules add Modbus serial, CANopen, Ethernet/IP or additional serial links when the application grows.
Electrical and Environmental
The module draws 24 V DC via the backplane, consumes 2.2 W and pulls 90 mA at 24 V DC. It operates from 0°C to +60°C, stores from -25°C to +70°C, tolerates 5% to 95% relative humidity (non-condensing) and carries an IP20 rating.
Physical
Dimensions are 100 × 28 × 93 mm and weight is 0.200 kg.
Where It Fits in the Field
Oil and gas operators, water utilities and OEM machine builders still run M340 installations across compressor control, pump stations and packaged skids. The BMXP341000 handles discrete interlocking, analog monitoring and Modbus serial links to drives, flow computers and panel instruments. Because the platform is compact and the I/O ceiling is generous, it remains a practical choice for retrofit work where the rack, wiring and program already exist.
Installation and Setup Notes
Mount the CPU in the main X80 rack and confirm the backplane supplies a stable 24 V DC. Keep the cabinet within the 0°C to +60°C operating window and avoid condensing humidity around the IP20 housing. Use EcoStruxure Machine Expert (Unity Pro) to load and verify the program. When wiring into a plant network through Modbus serial, confirm cable pinouts and any gateway or connection module with your supplier before commissioning.
Lifecycle Status and Sourcing
Schneider lists this CPU as discontinued, with end of sale on 2020-11-01 and migration guidance toward M580 or the current M340 range. For plants that need to keep existing racks running, sourcing a verified BMXP341000 is often faster and cheaper than a full migration. Please verify current lifecycle status and availability with Oil AutoTech before ordering.
Integration Note
Modbus Serial RTU/ASCII works directly over the built-in RJ45 port. For Ethernet/IP or CANopen connectivity, an X80 communication module is required; confirm the correct module and cabling with the supplier.
Choosing the Right Module
Before you buy, confirm the rack size, the discrete and analog point count your program uses, and whether your network needs an optional communication module. Oil AutoTech offers hands-on technical selection help and fast dispatch, worldwide, so you can match the CPU to your existing installation. Contact Oil AutoTech today for pricing and availability.
