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Automation & Control

Automation & Control: PLCs, DCS Systems, CNC Controllers & More

Industrial automation and control systems are the operational backbone of manufacturing plants, process facilities, and critical infrastructure. PLC Direct supplies surplus sealed, refurbished, and used automation and control hardware across installed industrial platforms, including programmable logic controllers, DCS systems, CNC controllers, industrial PCs, and remote I/O modules. Components are stocked across leading brands to support maintenance and lifecycle continuity for installed industrial systems.

Where Are Automation & Control Systems Used in Industrial Environments?

Automation and control hardware is deployed wherever industrial processes require precise sequencing, real-time monitoring, or machine-level coordination. Facilities and operations that depend on this equipment include:

Discrete manufacturing plants running PLC-controlled assembly, machining, and packaging lines.

Process industries, including chemical, petrochemical, and pharmaceutical facilities, using DCS systems for continuous process control.

CNC machining and fabrication operations dependent on CNC controllers and CNC circuit boards for precision cutting, milling, and turning.

Water and wastewater treatment facilities using remote I/O modules across distributed pump stations and treatment stages.

Mining and mineral processing operations using industrial PCs and fieldbus controllers for SCADA-connected automation.

When a failed controller or I/O module halts production, fast access to a stocked replacement keeps facilities running on schedule.

Which Brands of Automation & Control Hardware Does PLC Direct Stock?

PLC Direct carries automation and control hardware across multiple leading industrial brands, covering PLCs, DCS systems, CNC equipment, and remote I/O platforms commonly found in installed industrial systems.

Siemens SIMATIC S7 Series and SINUMERIK CNC: SIMATIC S7-300 and S7-400 PLC modules, ET 200SP remote I/O hardware, and SINUMERIK CNC controllers and CNC circuit boards for installed Siemens systems.

Schneider Electric Modicon PLCs and Remote I/O: Modicon M340, M580, Quantum, and Premium platforms, with Modicon Momentum distributed I/O for remote I/O replacement applications.

ABB AC500 PLC Family: AC500-eCo, AC500 standard, AC500-XC, and AC500-S safety controllers, stocked alongside S500 I/O modules and communication modules.

Mitsubishi Electric MELSEC PLCs: MELSEC Q Series and iQ-R Series programmable logic controllers and I/O modules for installed Mitsubishi Electric automation systems.

Omron Sysmac and CJ Series: Sysmac NX Series CPUs and CJ Series modular PLC hardware for replacement and maintenance of installed Omron control systems.

All automation and control hardware listed above is available as surplus sealed, refurbished, or used, providing condition-grade options to match both budget and application requirements.

What Should You Know Before Ordering Automation & Control Hardware?

Hardware condition options: Hardware is supplied as surplus sealed, refurbished, or used. Surplus sealed units are factory-sealed and undeployed; refurbished units have been tested and restored to operational condition; used components are pulled from service and sold as-is under the standard PLC Direct warranty.

Compatibility and part identification: PLC modules, DCS I/O cards, CNC circuit boards, and remote I/O hardware are platform-specific. Confirm the exact part number, controller series, and communication protocol (PROFIBUS, EtherNet/IP, Modbus TCP/IP) before ordering. For CNC systems, verify the controller generation, as circuit boards and drive modules are not interchangeable across generations.

Warranty: All automation and control hardware purchased from PLC Direct carries a standard 1-year PLC Direct warranty covering defects and functionality, applicable to surplus sealed, refurbished, and used products.

PLC Direct supplies automation and control hardware for replacement and maintenance purposes and does not provide system design, programming, or integration services.

Frequently Asked Questions

PLC Direct stocks programmable logic controllers, DCS I/O and controller modules, CNC controllers and CNC circuit boards, industrial PCs, remote I/O modules, fieldbus controllers, and PLC communication modules, supplied as surplus sealed, refurbished, or used across multiple industrial brands.

Yes. PLC Direct stocks CNC circuit boards, CNC controllers, and CNC drive modules for replacement and maintenance in installed CNC machining systems. CNC hardware is platform-specific, so confirm the controller generation and board part number before ordering.

A programmable logic controller handles discrete machine control, covering sequencing, interlocking, and machine-level automation where fast scan times are critical. A distributed control system is designed for continuous process control across large operations, such as chemical plants or refineries, where multi-loop control and integrated process management are the primary priorities. Many facilities run both platforms across different areas of the same operation.

PLC Direct supplies automation and control hardware as surplus sealed, refurbished, or used. Surplus sealed units are factory-sealed and undeployed; refurbished units have been tested and restored to operational condition; used components are pulled from service and carry the standard 1-year PLC Direct warranty. The appropriate condition grade depends on system criticality, budget, and whether the part is going into active service or being held as a maintenance spare.

All automation and control hardware purchased from PLC Direct is covered by a 1-year PLC Direct warranty applicable to surplus sealed, refurbished, and used products, covering defects and functionality. PLC Direct does not offer programming, configuration, or integration services.