A common implementation of Cascade Control is where a flow controller receives setpoint from some other process controller (pressure,temperature,level,analytical etc) ,fluid flow being one of the fastest responding process types is existence. A feed water control system for a steam boiler is one such example. The secondary or slave controller(flow)...

Fig:Heat Exchanger Here's how a heat exchanger shown in the above diagram works. Here CO is the controller output,PV is the process variable i.e temperature of the water.The control valve on the cooling liquid line respond to the temperature variations of the water at the output of the heat exchanger.As the temperature at the outlet begins to rise...

What is a CASCADE control loop.? To shield the  effect of disturbances as in feedback control loop,we have a CASCADE control loop. A CASCADE control loop is a loop within a loop, Primary loop and a Secondary loop.The Primary loop acts first as soon as it experiences some kind of disturbance before being fedback to the main controller.Hence...

What is a PID? A Process to work in Automatic mode must be properly tuned for optimum performance.If the parameters tuned are incorrect ,then there would be wastage of resources.The Process we dealt with in the previous page (i.e heat exchanger) forms the base of process control.More complex loops are present in addition to feedback control..It is...

What is a Process? Well,I have the simplest of the definations.A Process Control is the act of controlling Final Control Element (FCE) such as a Control valve which changes the manipulated variable to control a process value. Terms related to Process Control. 1.Controller Output(CO):It is the Output of Controller.i.e Setpoint(SP)-Process value(PV). 2.Final...