In the world of industrial control, a "free download" of a major SCADA platform is almost always a trap for the unwary. The real cost is your security and reliability. Always go through the official vendor portal.
It scales from small, standalone machines to massive industrial sites with thousands of I/O points. intouch scada software free download
If your goal is learning SCADA concepts without the Aveva ecosystem, these are 100% free and legally downloadable: In the world of industrial control, a "free