Technology as it started is not the technology as we know it today
Technology as it started is not the technology as we know it today.
So we should start learning from scratch and design a control system which probably used less technology because that is what most of the electronic components work with fieldbus technology.
Fieldbus technology multiple components are compatible, each component has a microprocessor, you have to lead communication between the variety of components within the control loop you have more of this plug in play adaptation of electronics that we are currently use.
You might also expect information can be readily shared across the variety of processes in the plan, so the decision for the controller be incorporate a significant amount of information, this is not always the case once upon time we did not even have electronics and control systems were based on pneumatic systems where air was the signal that was sent to the control valve or sent through the plane using airlines, so in the 1920s the majority of processes were replaced with pneumatic control systems.
In 1950s electronic starting to become available with the development of transistors, resistors, and capacitors, also instead of using air signals through the plant, all wires could be used to transmit signals.
The first electronic analog systems were introduced in 1959; it was incorporated with oil refinery type processes.
In 1970s the distributed control system were developed and distributed the advantage there is that distributed control systems are based on a digital signal, so a variety of different components could be integrated together in ways that allow for information sharing data storage troubleshooting.
Today fieldbus technology is in development and being incorporated into control systems.
Pneumatic control systems, the general idea is that we have air that is going to be the signal that is sent to the valve and also sent through the entire control process.
So air is transported through the pipes, then it goes to valves and have these systems that are developed based on bellows battles and nozzles, this use compressed air to integrate proportional-integral-derivative (PID) or control action in the controller.
In the 1950s with the early stage development of electronics such as resistors, capacitors, and transistors.
PID control and transmission of signals could be done now using wires and electrical signals instead of air signals obviously a wire relative to an airline is significantly cheaper.
The use of electric signals also allows some development or some integration of advanced controls beyond just PID feedback in that ratio feed-forward and other methods can be incorporated.
In the end of 1950s early of 1960s, computer control system were developed, these systems combined a variety of electronic analog systems, in a way where information can be easily shared.
The main problem with these types of systems, as all the controllers were connected to a single computer, there for it had major reliability issues so there you could have redundant computer system setup but still reliability was as issue, because everything was connected together if one component failed the entire system would have to be down.
Now with the development of distributed control systems we are started to approach that the level of control that we would develop if we were going to do such a thing today, so the distributed control systems (DCS), were developed in the 1970s, these systems involved our integrated redundant microprocessors so each individual control system could effectively have its own control loop.
The data was stored digitally, so the analog signals from the transmitter were converted to a digital signal, and these digital signals were stored and processed with in a central unit, and used by the controller to control processes individually.
In all of these systems like DCS and supervisory computer control systems there are a lot of challenges with compatibility.