Industrial PCs for PLC Communication: What You Need to Know

Quick Answer

Industrial PCs provide a reliable computing layer between PLCs, sensors, machines, and higher-level manufacturing software. The right industrial PC should support the required communication interfaces and protocols while delivering stable 24/7 operation. For PLC communication projects, BVS Industrial PCs combine flexible I/O, industrial-grade construction, fanless cooling, and configurable processing power to support automation, data acquisition, HMI, and Industrial IoT applications.

How Industrial PCs Communicate with PLCs

A PLC is designed primarily for deterministic machine control, while an industrial PC provides additional computing, visualization, data processing, networking, and software capabilities.

In a typical automation architecture, the industrial PC sits between field devices and higher-level systems:

Sensors / Actuators
        ↓
      PLC
        ↓
Industrial PC
        ↓
HMI / SCADA / MES
        ↓
Cloud / Enterprise Systems

The PLC handles real-time control logic, while the Industrial PC can collect operational data, run visualization software, perform analytics, store production information, or communicate with remote systems.

Common PLC Communication Interfaces

The exact interface depends on the PLC manufacturer and application. Common industrial communication methods include:

• RS232 – Suitable for short-distance point-to-point communication.

• RS485 – Common in industrial environments and suitable for longer-distance multi-device communication.

• Ethernet – Provides high-speed network connectivity between industrial computers, PLCs, switches, and servers.

• USB – Often used for peripherals, data transfer, or configuration tools.

• Digital I/O – Useful when the computer needs to interact directly with external devices.

• Industrial Ethernet protocols – Depending on the PLC and software ecosystem, systems may use protocols such as Modbus TCP, EtherNet/IP, PROFINET, or OPC UA.

The important point is that hardware interfaces and communication protocols are related but not identical. Having an Ethernet port, for example, does not automatically mean that an industrial PC supports every industrial Ethernet protocol.

Key Features and Specifications for PLC Communication

Choosing an Industrial PC for PLC integration requires more than looking at CPU performance. The system should be evaluated as part of the entire automation architecture.

1. Multiple COM Ports

Serial communication remains widely used in industrial automation because many PLCs, meters, controllers, barcode scanners, and legacy machines rely on RS232 or RS485.

An Industrial PC with multiple COM ports can reduce the need for additional serial expansion hardware.

For projects involving several controllers or machines, consider:

• Number of COM ports

• RS232/RS485 support

• Isolated vs. non-isolated serial interfaces

• Connector type

• Communication speed

• Multi-device requirements

2. Dual or Multiple LAN Ports

Industrial PCs with multiple Ethernet ports can separate different networks or connect simultaneously to PLCs, industrial switches, SCADA systems, and enterprise networks.

For example:

LAN 1 → PLC / Machine Network
LAN 2 → Factory / MES Network

This architecture can help simplify network segmentation and system integration.

BVS offers industrial computer configurations with multiple LAN and COM interfaces for applications such as factory automation and industrial control. Its product range includes models specifically positioned for automation applications, including the BVS GW-G Industrial Computer with multiple COM and LAN ports. 

3. Fanless Thermal Design

Factory environments can expose computers to dust, vibration, and continuous workloads. A fanless industrial PC uses passive thermal dissipation instead of a mechanical cooling fan.

This can reduce the number of moving parts and limit dust intake while supporting continuous operation.

BVS fanless industrial computers use metal chassis designs that also help dissipate heat, making them suitable for demanding industrial deployments. 

4. Processor and Memory

PLC communication itself may not require a high-end processor. However, the Industrial PC often performs additional tasks.

For example, one system might simultaneously run:

• PLC communication software

• HMI visualization

• SCADA client

• Database services

• Data logging

• Remote monitoring

• Edge analytics

In these cases, an Intel Core i3, i5, or i7 configuration with appropriate RAM may provide more practical headroom than selecting a system based only on the communication requirement.

5. Storage and Operating System

SSD storage is generally preferable for industrial systems because it has no mechanical moving parts and offers fast access.

Operating system selection is equally important. Windows-based Industrial PCs can be convenient when the automation project relies on Windows-compatible HMI, SCADA, database, or engineering software.

BVS provides configurable industrial computers supporting Windows and Linux options across different models, allowing system integrators to match the platform to their software environment. 

Application Scenarios for Industrial PCs and PLC Communication

Factory Automation

This is one of the most common applications.

An Industrial PC can collect production information from multiple PLCs and display machine status through an HMI or SCADA interface. It can also record production counts, alarms, machine states, and process parameters.

For example:

PLC → Industrial PC → SCADA → MES

The PLC remains responsible for machine control while the Industrial PC provides the computing and visualization layer.

Smart Manufacturing

In Industry 4.0 environments, PLC data increasingly needs to be connected to manufacturing software and analytics platforms.

An Industrial PC can act as an edge computing node that collects data locally before forwarding selected information to MES, ERP, or cloud platforms.

This approach can reduce unnecessary data transmission while enabling local monitoring and analysis.

BVS identifies smart manufacturing, industrial automation, and MES terminals among its industrial application scenarios. 

Medical Equipment

Industrial computing platforms can also be integrated into medical and laboratory equipment where reliable communication with controllers, sensors, and instruments is required.

A compact Industrial PC can provide the processing and user-interface layer while dedicated controllers handle specific equipment functions.

The exact computer configuration should be selected according to the equipment's communication interfaces, operating environment, certification requirements, and software architecture.

Self-Service and Smart City Systems

PLC communication is not limited to factories.

Industrial PCs can also communicate with controllers used in parking systems, transportation equipment, building automation, environmental monitoring, and self-service infrastructure.

BVS lists transportation, self-service kiosks, and smart city applications among the environments supported by its broader hardware solutions. 

Buying Considerations: How to Select an Industrial PC for PLC Communication

Step 1: Identify the PLC Interface

Start by determining exactly how the PLC communicates.

Ask:

• Does it use RS232 or RS485?

• Is Ethernet required?

• Which industrial protocol is used?

• How many PLCs need to connect?

• Is protocol conversion required?

This prevents purchasing a computer with unnecessary processing power but insufficient I/O.

Step 2: Calculate the Total Workload

Do not size the Industrial PC based only on PLC communication.

Consider all software that will run simultaneously. A simple data gateway may require modest hardware, while a system combining SCADA, database storage, machine vision, and edge AI may require substantially more CPU, RAM, and storage.

Step 3: Match the Environment

Consider the actual installation location:

• Operating temperature

• Dust and humidity

• Vibration

• Available cabinet space

• Power input

• Mounting requirements

For factory-floor installations, a compact fanless Industrial PC can be advantageous because passive cooling eliminates a mechanical fan and supports a more rugged enclosure design.

Step 4: Plan for Expansion

Industrial automation projects often evolve.

If additional PLCs, sensors, displays, cameras, or network devices may be added later, leave sufficient I/O and processing headroom.

The best Industrial PC is not necessarily the one with the highest specification—it is the one whose interfaces, performance, thermal design, and lifecycle match the complete automation system.

FAQ

1. Can an Industrial PC communicate directly with a PLC?

Yes. An Industrial PC can communicate directly with a PLC through supported interfaces and protocols such as RS232, RS485, Ethernet, Modbus, OPC UA, or other protocol stacks, depending on the specific equipment and software.

2. Which Industrial PC is best for PLC communication?

The best model depends on the PLC interface, protocol, number of connected devices, software workload, operating environment, and required I/O. For basic PLC gateways, a compact system may be sufficient; more demanding SCADA, vision, or edge computing applications may require higher CPU and memory configurations.

3. Is RS485 better than Ethernet for PLC communication?

Neither is universally better. RS485 is useful for many legacy and serial-based industrial devices, while Ethernet generally provides higher bandwidth and easier integration with modern network architectures. The PLC and protocol requirements should determine the choice.

4. Can a fanless Industrial PC run PLC and SCADA software?

Yes. A properly configured fanless Industrial PC can run PLC communication software, HMI, SCADA, data logging, and other industrial applications. The required processor, RAM, storage, and operating system should be selected according to the complete workload.

5. Can Industrial PCs connect PLC data to the cloud?

Yes. An Industrial PC can serve as an edge gateway, collecting PLC data locally, processing or filtering it, and forwarding selected information to cloud or enterprise platforms. This can create a bridge between machine-level control and higher-level digital systems.

Explore BVS Industrial PC Solutions

BVS provides Industrial PCs and embedded computing platforms for factory automation, machine control, Industrial IoT, edge computing, and other industrial applications. Its product portfolio includes fanless Mini PCs with configurable processors, RAM, storage, LAN, COM, and other I/O options. 

Industrial PC Product Range:

BVS GW-B Plus Fanless Industrial Mini PC:

BVS GW-D Industrial Mini PC:

Related BVS Articles

Why Local Data Processing Is Critical in Modern Manufacturing

How Fanless Industrial Computers Reduce Downtime

RS232 vs RS485: What's the Difference and Which Serial Port Should You Choose?

For PLC communication projects requiring specific COM, LAN, processor, storage, or mounting configurations, contact BVS to discuss your application requirements and select a suitable Industrial PC configuration.