Classical mechanics (often called Newtonian mechanics in honor of…
Perhaps the most important rule of controller tuning is to know the…
An electric motor is often used as a discrete control element in a…
Process measurements are often of an analog nature: the temperature of…
A fluid is any substance having the ability to flow: to freely change…
The purpose of a control valve actuator is to provide the motive force…
Suppose we wished to measure the rate of propane gas flow through a…
Many years ago, when I was first learning about electricity, I…
“Radio” systems use electromagnetic fields to communicate…
A wise PLC programmer once told me that the first thing any aspiring…
A control strategy similar to ratio control is relation control. This…
Once while working as an instrument technician in an aluminum foundry,…
Disconnect Switches Disconnects are switches designed to isolate…
Control strategies such as cascade, ratio, feedforward, and those…
A very simple device used to measure pressure is the manometer: a…
“Polyphase” means “many phases,” describing a…
All masses require force to accelerate (we can also think of this in…
While 50 and 51 (instantaneous and time overcurrent) relay functions…
A fundamental limitation of proportional control has to do with its…
The vast majority of PID controllers in service today are digital in…
Up until this point, we have explored various types of instrumentation…
In some process applications, it is important that the control valve…
A 4 to 20 mA current signal represents some signal along a 0 to 100…
Visualizing the actions of P, I, and D tuning parameters using graphs…
An electric motor is often used as a discrete control element in a…
