Product Details

MODICON PC-0984-385 is a mid-range programmable controller and main processor within the classic Modicon 984 series, acting as the central logic core for legacy distributed automation racks. This unit executes standard LL984 ladder logic, collecting discrete and analog signals from field sensors, running user-defined control routines, and issuing output commands to actuators, valves and contactors for continuous process regulation. It integrates an internal power supply and supports a combination of Modbus and Modbus Plus communication ports, enabling data exchange with operator panels, remote I/O drops, SCADA hosts and other Modicon controllers over industrial networks. It supports a generous user logic memory pool and delivers stable scan performance for conventional and moderately complex automation tasks, while a built-in real-time clock assists with timestamping alarms and scheduled sequence operations. The processor supports expansion to multiple local racks and pairs well with S908 remote I/O adapters to extend control points across large factory layouts. A lithium backup battery preserves user programs and runtime register values during unexpected power loss. Front panel LED indicators display run status, system faults, battery warning and network traffic, allowing maintenance engineers to quickly pinpoint communication breakdowns or hardware anomalies on site. Integrated EMI filtering and surge suppression circuits protect the backplane bus and communication interfaces from voltage spikes and electromagnetic interference produced by inverters, contactors and heavy power cabling. Programming and online monitoring are completed via Modsoft or ProWORX 32 software. As an obsolete industrial spare part, this main processor is critical for sustaining aging Modicon control systems. Direct drop-in replacement keeps the existing ladder program, I/O mapping and network configuration unchanged, cutting commissioning time and lowering production downtime.

Basic Parameters

Product type: 984 series PLC main processor

Part number: PC-0984-385

Brand: Modicon, Schneider Electric

Power input: 120 / 220 VAC, 0.5 / 0.25 A

Communication: Modbus, Modbus Plus

Instruction set: LL984 ladder logic

Expansion: compatible with 800 series I/O racks and S908 remote drops

Data retention: lithium backup battery

Weight: 2.41 kg

Max altitude: 1000 m without derating

Operating temperature: 0°C ~ +40°C

Protection grade: IP20

Supported Functions

Execute LL984 ladder logic for industrial process automation

Bidirectional data exchange over Modbus and Modbus Plus

Real-time clock for alarm time stamping and timed sequences

Cyclic reading and refreshing of local and remote I/O points

Battery-backed preservation of user program and runtime data

System self-diagnosis and fault status flag output

Core Functions

Serve as a reliable programmable controller for legacy automation racks

Visual LED indication for fast processor and network troubleshooting

Act as the central main processor for Modicon distributed control

Work as a stable logic core for continuous production process control

Support multi-rack expansion and remote I/O networking

Modular replacement for failed primary controllers of 984 systems

Hardware Specifications & Environmental Features

Circuit design: integrated EMI filter and communication port protection

Storage temperature: -25°C ~ +70°C

Relative humidity: 5% to 80% 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 rack compatibility, backup battery health, communication parameters and I/O expansion layout before ordering.

This is from our current stock.

available stock.xlsx