When starting a SCADA project, many people's first instinct when choosing an embedded industrial computer is: How powerful should the CPU be? How much memory? ARM or X86?

These are certainly important, but they shouldn't be the first step.

A more practical selection method is to first determine: ‌Where exactly will the SCADA run?‌

Because behind the statement "I need SCADA" can lie three completely different types of requirements:

The first: You only need to collect data from PLCs and meters at the equipment site and create simple screens and alarms.
The second: You need to run traditional SCADA software like KingView or WinCC directly on the embedded industrial computer.
The third: You need to collect data from hundreds of devices and then send it to a central SCADA, MES, or cloud platform.
These three needs place very different demands on the embedded industrial computer.

1. First, Determine: Do You Need Local SCADA or Central SCADA?

Before choosing a model, draw a simple architecture diagram.
For example:
PLC / Meters → Industrial PC → SCADA‌
Then determine on which layer the SCADA resides.
If the embedded industrial computer itself is only responsible for collecting data from PLCs, meters, and sensors, processing it through protocols like Modbus, OPC UA, MQTT, and then sending it to the SCADA running on a server, then the embedded industrial computer is essentially playing the role of a ‌SCADA Edge Computer‌.
In this scenario, the requirements for on-site interfaces, protocols, and network reliability are often more important than the ability to run large desktop software.
However, if you plan to install Windows SCADA software directly on the embedded industrial computer and also run databases, historical trends, alarms, reports, and web services, you should prioritize an X86 Industrial PC.
So, you can remember this first rule directly:
If SCADA is on the server, prioritize ARM for the on-site Industrial PC. If SCADA is installed directly on the Industrial PC, especially Windows SCADA, prioritize X86.‌

2. For On-site Data Acquisition and Local Monitoring Only, ARM is Often More Cost-Effective

Let's assume you are an equipment manufacturer.
Your equipment contains a Siemens PLC, several Modbus RTU meters, and some sensors. The customer wants to add a local monitoring page while also uploading equipment status, alarms, and production output to a remote platform.
For this type of project, there's no need to start with a high-performance X86 system right away.
For example, the USR-EG528 is itself an ARM Linux Industrial PC. It uses a quad-core Cortex-A53 processor and Ubuntu 24.04, comes with 4GB RAM, 32GB eMMC, and integrates WukongEdge and Node-RED. More importantly, it has a built-in ‌Local SCADA/HMI‌, allowing for direct on-site data acquisition, monitoring, and control. 
The EG528 supports PLCs like Siemens, Mitsubishi, Omron, Delta, Fatek, and Modbus, as well as industrial protocols like IEC 61850, IEC 104, DL/T645, DNP3.0, and BACnet. On-site interfaces include 4 serial ports, dual Ethernet, USB, and HDMI.
Therefore, if the main requirements are:
PLC Data Collection + Protocol Conversion + Local Screen + MQTT/OPC UA + Remote Monitoring‌

Then an ARM Industrial PC like the EG528 is usually the more cost-effective choice.
There's no need to jump straight to a Core i5 just because of the word "SCADA."

3. To Run Windows SCADA Like KingView or WinCC, Choose X86 Directly

If your SCADA is already confirmed to run on Windows, the selection process actually becomes simpler.
For example, PUSR KingView itself is a Windows-based SCADA that can perform real-time data acquisition, historical data storage, visualization, and data forwarding, supporting up to 60,000 Tags and providing 4,000+ device drivers. 
In this case, it is not advisable to force the use of ARM just to reduce hardware costs.
Because what is truly expensive is often not the embedded industrial computer itself, but the cost of software migration.
If the existing PLC drivers, databases, report programs, ActiveX components, or project files were all developed around Windows/X86, the engineering cost of re-adapting them after switching architectures can easily exceed the hardware price difference.
The PUSR EC100, EC300, and EC500 all use the X86 architecture industrial pc, support both Windows and Linux, and feature an all-aluminum fanless industrial design suitable for 24/7 operation. 
For a standard SCADA workstation, you can first look at the ‌EC100‌.
It uses an Intel Celeron J6412, with 8GB RAM, 128GB storage, dual Gigabit Ethernet ports, 2 RS232/RS485 ports, and 4 USB 3.0 ports, while also supporting dual HDMI output. 
If you are only running a regular SCADA project, connecting to PLCs, displaying screens, and saving historical data, this level of hardware can typically cover many equipment projects.

4. When a SCADA Project Grows, Look at Data and Interfaces First, Don't Just Upgrade the CPU

If the site expands from a single production line to an entire workshop, the requirements might become:
5 PLCs, 20 meters, barcode scanners, vision systems, MES, SCADA server, all while connecting to the corporate network.
At this point, what often starts to influence the selection is the ‌number of interfaces and network connections‌.
For example, the EC300 provides dual Gigabit Ethernet ports, 2 RS232/RS485 ports, 4 RS232 ports, and more USB ports. The EC500 further increases this to ‌5 Gigabit Ethernet ports, 4 RS232/RS485 ports, and 4 RS232 ports‌. 
Therefore, if the SCADA needs to span multiple networks simultaneously, for example:
Equipment Network / PLC Network / MES Network / Corporate Network / Remote Maintenance Network‌
Then the value of EC500's multiple network ports might be greater than simply increasing the CPU clock speed.
Equipment manufacturers can create a very simple table before selecting a model:

Once you fill out this table, you can usually eliminate a large portion of embedded industrial computer models.

5. If the SCADA is Right on the Equipment Panel, Consider the SH800

There is another scenario often mistakenly thought to always require:
PLC + Industrial PC + HMI‌
Three separate devices.
In reality, if the SCADA's main purpose is data display, parameter setting, alarm viewing, and simple control right next to the equipment, you can consider combining the Industrial PC and HMI.
The USR-SH800 is a 10.1-inch Industrial Panel PC. It uses an ARM Cortex-A55 platform, is configured with 4GB RAM and 32GB eMMC, runs Ubuntu, and supports WukongEdge, Node-RED, and Docker. Interfaces include 2 RS485 ports, 2 RS232 ports, dual Ethernet, and USB. 
Its positioning is more suitable for:
Equipment Data Acquisition + Local Visualization + Touch Operation + Edge Computing‌
In other words, if a customer says "I need SCADA," but in reality only needs an operational screen mounted on the equipment, there's no need to first purchase a separate embedded industrial computer and then add an HMI on top.
This integrated solution often saves space inside the cabinet and reduces wiring.

6. For Energy SCADA, Don't Just Look at the SCADA Software

Energy storage, photovoltaic, and microgrid projects are different again.
For example, an energy storage cabinet might simultaneously contain:
BMS, PCS, electricity meters, temperature control, fire protection, access control, temperature/humidity sensors, and various DI/DO signals.
If you choose a standard PC just because "it needs to connect to SCADA," you'll quickly find that you don't have enough serial ports, CAN ports, and I/O, forcing you to add serial servers, I/O modules, and protocol gateways.
For such projects, you can directly consider the ‌EG828-EMS‌, which is designed specifically for energy scenarios.
The EG828-EMS integrates 8 isolated RS485 ports, 2 CAN ports, 16 isolated GPIOs, 6 relays, and various analog interfaces. It also provides 4G, Wi-Fi 6, and Gigabit Ethernet for connecting devices like BMS, PCS, thermal management systems, and fire protection equipment, and uploading data to the EMS platform.
In the remote island microgrid case provided on the PUSR website, the site needed to coordinate different energy devices like photovoltaics, energy storage, and diesel generators simultaneously and address the issue of frequent manual battery checks. This architecture uses gateways to handle multi-device access and local energy dispatch. 
When selecting an Industrial PC for such projects, ‌protocol and on-site I/O are often more important than desktop computing performance.‌

7. In Real Projects, the SCADA Front End Doesn't Necessarily Need a Large PC

A photovoltaic power station project provided by PUSR is a typical example.
In the project, the industrial pc EG628 directly collects DL/T645 data from inverters, converts it locally to MQTT, and uploads it to the IoT platform, eliminating the need for an additional independent protocol gateway. The project result cited in the material was a 60% reduction in deployment time and a 45% reduction in operational costs. 
This case is very instructive for SCADA selection.
The on-site Industrial PC doesn't necessarily have to handle everything.
Often, a more reasonable architecture is actually:
PLC / Meters → ARM Industrial PC → Central SCADA‌
The ARM device is responsible for protocols, data acquisition, edge computing, and data organization; the server handles large-scale SCADA, historical databases, and reporting.
This results in lower on-site hardware costs and a system that is easier to scale.

8. You Can Select Directly Using This Method

If you are currently selecting an embedded industrial computer for a SCADA project, you can refer directly to:

Finally, let's return to the initial question:

Which industrial PC should I use for SCADA?‌
The answer is not simply "ARM" or "X86."
If the SCADA is mainly responsible for on-site data collection and simple visualization, prioritize ARM Industrial PCs like the EG528.

 If you need to run Windows SCADA, databases, and traditional industrial software, prioritize X86 Industrial PCs from the EC series.

 If you need a screen, consider the SH800.

 For energy storage and microgrids, you should first check the number of RS485, CAN, DI/DO ports, and protocols, then consider the EG828-EMS.

The truly suitable SCADA embedded industrial computer is not the one with the highest performance.
It's the one ‌that can run your SCADA software, connect to your field devices, withstand the industrial environment, and doesn't make you pay for performance you won't use.‌