The PLC versus IPC or PC-based control debate has been with us for over two decades now, with commentators making various predictions about the rise of industrial controllers with PC-based internals versus purely PLC solutions. Yet according the latest figures from Gambica the PLC market continues to grow. Mitsubishi Electric, for example, has long been a global leader in PLC technology with a massive installed base and a continuous stream of innovations being released to the market.
It is interesting to note that there has been some blurring of the technologies, with each now incorporating some of the features of the other. From the PLC perspective, this includes everything from the inclusion of embedded web servers to the availability of plug-in PC modules such as Mitsubishi Electric’s C-Controller. Other modules, such as Mitsubishi Electric’s MES module, mean that PLCs can now link directly to higher level systems without the need for intermediate PC hardware. Furthermore, the combination of PLCs and HMIs means that PLC platforms can also provide a very PC-like environment for SCADA and other visualisation applications.