Product Details

Modicon ALU151-1 is a reliable a250 base cpu processor and dedicated modnet 1 controller for the AEG Modicon A250 modular rack platform, the original base-level CPU variant of the A250 family, programmed by Dolog AKF125 software. This eprom legacy plc cpu occupies the leftmost slot on the A250 backplane and supplies 5 VDC power for the local rack; program storage relies on a pluggable EPROM cartridge instead of battery-backed RAM, so no backup battery is fitted on the module itself. It integrates native Modnet 1 / SFB network interface and an RS232 programming port, supporting peer-to-peer network communication with other A250 stations, HMI and supervisory hosts. It scans all matched A250 discrete, analog and specialty I/O modules, executes control logic and delivers output commands to field actuators. The front panel carries clear status LEDs for run, fault, network activity and diagnostic codes for fast on-site troubleshooting. With conformal coated PCB and industrial-grade components, this CPU can sustain continuous operation in dusty, vibrating and electrically noisy process plant environments. As a discontinued legacy spare, this a250 base cpu processor serves as a drop-in replacement to restore core logic and Modnet network operation for ageing Modicon A250 automation racks.

Basic Parameters

Brand: Modicon (AEG / Schneider legacy)

Model: ALU151-1

Product Type: A250 Base PLC CPU Processor

Compatible Rack: Modicon A250 dedicated backplane and chassis

Programming Software: Dolog AKF125

Memory Type: EPROM cartridge, no onboard backup battery

Network: Built-in Modnet 1 / SFB interface

Programming Port: RS232 serial port

Rack Power: Provides 5 VDC to local backplane

Mounting: Single-slot rack installation, leftmost CPU position

Indicator: Front LED for run, fault, network and diagnostic status

Product Status: Discontinued, end of original production

Net Weight: Approximately 0.50 kg

Supported Functions

This a250 base cpu processor runs cyclic scanning of user control logic and all connected A250 I/O modules. The modnet 1 controller supports timer, counter, arithmetic, comparison and PID closed-loop regulation for temperature, flow, pressure and liquid level control. This eprom legacy plc cpu exchanges real-time discrete and analog tags across the Modnet 1 network for cross-station interlocking, and accepts program upload and download through its RS232 port. It supports sequential batch control and alarm handling, and runs built-in diagnostics to detect bus failure, network error and EPROM cartridge fault. When critical faults are triggered, it forces outputs to predefined safe states to protect field equipment. It works cooperatively with the full lineup of A250 series I/O and communication modules to build a complete distributed control system.

Core Functions

As the base central processor for the A250 platform, this a250 base cpu processor interprets the EPROM-resident control program, collects field I/O signals and drives actuators. Its native Modnet 1 port enables legacy plant-wide distributed networking, while the EPROM design guarantees program retention without battery maintenance. This modnet 1 controller works as a direct spare to rebuild the core control brain for ageing Modicon A250 automation racks.

Hardware Specifications & Environmental Features

Operating Temperature: -10°C ~ +60°C

Storage Temperature: -20°C ~ +70°C

Relative Humidity: 5%–95%, non-condensing

Housing: Rugged metal framed single-slot module

Protection: Hardware watchdog, transient suppression for network and serial lines

Anti-interference: Isolated communication circuits, conformal coated vibration-resistant PCB

Compatibility: Modicon A250 chassis, A250 I/O modules, Modnet 1 network nodes

Industry Applications: Applied in legacy petrochemical distributed control, old paper making production automation, material handling conveyor lines, packaging and textile machinery, water treatment remote signal collection and large conveyor remote I/O control racks.

Note: Confirm A250 backplane position, correct EPROM cartridge, Modnet 1 node address and Dolog AKF125 program compatibility before ordering.

This is from our current stock.

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