Standardizing to IEC 61131

“End users are now increasingly requiring that their specific applications are standardized to IEC 61131 and often write their own function blocks. This allows them to keep control of their programs, while making it easier to change suppliers and train up new personnel. As a result, software houses are using it more and more, which in turn places a demand on hardware manufacturers to increase the memory capacity on their PLCs (the Mitsubishi FX3U, for instance, has eight times the memory capacity of its predecessor).”