Industrial Controller Vs Prototype Controller(Study level Controller)

Question

What is the difference between industrial Controller and prototype(Study)level controllers or Raspberry pi/Arduino Vs. Industrial Controllers(PLC, NON PLC) controllers

Answer 1

Industrial controllers are driven by really intense quality requirements. For example, a single controller may be responsible for a bioreactor growing a batch of culture worth $1,000,000USD to a manufacturer. Industrial controllers have to run for months and months without failure.

In contrast, prototype, hobby and study controllers such as the Raspberry Pi and Arduino are designed to support exploration and teaching. Although quality is important, it is not a primary concern. For Raspberry Pi controllers, ease of use is paramount. Raspberry Pi excels at ease of use and is a rich platform for experimentation.

Here's a specific example. Modern industrial controllers support web services for configuration, monitoring and maintenance. And when I set up my Raspberry Pi controller for aeroponics, I also use web services for the same reason. The Raspberry Pi supports many web servers and I chose NodeJS, which is based on Javascript. Javascript is an interpreted language with automatic memory management. Javascript is a wonderful language for experimentation and exploration. So is Python. But interpreted languages tend to die for mysterious reasons related to memory leaks and fragmentation. Which means my Raspberry Pi dies every now and then for mysterious reasons and has to be rebooted.

These failures that I accept for the Raspberry Pi would be unacceptable for an industrial controller. For industrial controllers, I would choose a C++ web server such as Mongoose, which is small, simple and quite robust. Now I could certainly run Mongoose on the Raspberry Pi, but Raspbian itself might not be best for industrial control. Industrial controllers tend to have custom-built and tightly managed operating systems created by Yocto

Industrial controllers are often subject to strict regulations, especially in the biotech sector, where mistakes can impact human life and welfare. Even simple things like enclosures are regulated. For example, an industrial controller enclosure is often subject to "waterproofness ratings".

Taken together, the stringent constraints on industrial controllers cost manufacturers and consumers a lot, but that cost provides high value in terms of safety and yield. Thankfully, many hobbyists are able to create controllers with equivalent functionality (but with less stringent quality) using MCUs such as Arduino and Raspberry Pi. Indeed the latter provide a fertile frontier of new ideas and techniques for all controllers.