Product Details

MODICON PC-A984-130 belongs to the Modicon 984 A120 compact series and serves as a reliable compact CPU controller and logic processor for small to medium legacy automation systems. This automation core executes LL984 ladder logic programs to collect discrete and analog field signals, run user-defined control algorithms, and send output commands to actuators, valves and contactors. It carries 4K words of user logic memory and 1920 register words, with a fixed scan speed of 5 ms per thousand instructions, which balances response speed and stable operation for conventional process and machinery control. It is fitted with one native Modbus RS232 port for connecting operator panels, programming terminals and remote SCADA nodes, and provides an auxiliary memory slot for optional 8-byte or 32-byte EEPROM storage to preserve key configuration data. The unit supports up to 256 mixed local I/O points and can extend to four expansion subracks to increase system I/O capacity for larger control demands. A built-in lithium backup battery protects user logic and runtime variables when power fails unexpectedly. Clear LED indicators on the front panel display ready status, run mode, battery low alarm and Modbus communication activity, helping maintenance technicians locate communication faults or memory anomalies quickly on site. Integrated EMI filtering and surge suppression circuits protect the serial communication port and internal logic circuits from voltage spikes and electromagnetic noise generated by inverters, contactors and heavy power cables in control cabinets. It can be programmed with Modsoft or ProWORX software for ladder logic editing, downloading and online monitoring. As an obsolete industrial spare part, this compact CPU controller is widely used to replace failed main processors on aging Modicon compact control racks. Direct drop-in replacement retains the original control program, I/O mapping and Modbus communication parameters, greatly cutting reconfiguration work and reducing production downtime.

Basic Parameters

Product type: compact PLC CPU controller

Part number: PC-A984-130

Brand: Modicon, Schneider Electric, AEG

Series: 984 A120 Compact

User logic memory: 4K words

Register memory: 1920 words

Scan speed: 5 ms / k logic

Max local I/O: 256 mixed points

Expansion: support up to 4 expansion subracks

Communication: 1 × Modbus RS232

Auxiliary storage: optional 8 / 32 byte EEPROM

Power supply: 24 VDC, 1 A

Data retention: lithium backup battery

Mounting: two-slot rack plug-in

Operating temperature: 0°C ~ +60°C

Protection grade: IP20

Supported Functions

Execute LL984 ladder logic for automated process control

Modbus serial communication with HMI, programmer and SCADA

Cyclic data exchange with local and expansion rack I/O modules

Battery-backed preservation of user program and runtime data

Module self-diagnosis and status flag output

Noise filtering and surge protection for serial communication lines

Core Functions

Serve as a stable compact CPU controller for legacy automation racks

Visual LED indication for fast CPU and communication troubleshooting

Act as a dedicated logic processor for continuous production control

Work as the central automation core for small and medium control systems

Support modular I/O expansion for retrofitted factory machinery

Maintain consistent process regulation for long-running industrial lines

Hardware Specifications & Environmental Features

Circuit design: integrated EMI filter and serial port protection

Storage temperature: -25°C ~ +70°C

Relative humidity: 5% to 95% non-condensing

Condition: obsolete original spare part, available stock

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 A120 rack compatibility, backup battery condition, Modbus baud rate and I/O expansion layout before ordering.

This is from our current stock.

available stock.xlsx