Any physical location in an industrial facility harboring the…
Sometimes we encounter a diversity of instrument signal standards in…
Three-phase AC is the dominant mode of electric power generation and…
Converting between disparate units of measurement is the bane of many…
The two “process variables” we rely on most heavily in the…
Once while working as an instrument technician in an aluminum foundry,…
The simplest form of 4-20 mA current loop is the type used to…
So far we have just looked at instruments that sense, control, and…
There are several different methods useful for causing an AC induction…
Virtually any mass above absolute zero temperature emits…
Many years ago, when I was first learning about electricity, I…
A very common method for directly controlling low flow rates of fluids…
“Radio” systems use electromagnetic fields to communicate…
A completely different way of measuring liquid level in vessels is to…
There are many process control applications in the industry where it…
A simple control system drawn in block diagram form looks like this:…
In addition to Ohm’s Law, we have a set of rules describing how…
Few areas of mathematics are as powerfully useful in describing and…
At the next OSI Reference Model layer (layer 4) is a set of protocols…
The following animation shows the calculus concepts of differentiation…
A very simple device used to measure pressure is the manometer: a…
Classical mechanics (often called Newtonian mechanics in honor of…
A technological advance introduced in the late 1980’s was HART,…
A powerful mathematical concept useful for analyzing practically any…
An variable-area flowmeter is one where the fluid must pass through a…
Nearly every technical course teaches and tests students on…
Impedance in a series circuit is the orthogonal sum of resistance and…
Filled-bulb systems exploit the principle of fluid expansion to…
There are many process control applications in the industry where it…
A flow switch is one detecting the flow of some fluid through a pipe.…
In a manually-controlled process, a human operator directly actuates…
An electric motor is often used as a discrete control element in a…
Suppose we wished to measure the consumption of propane over time for…
Developed by the Modicon company (the original manufacturer of the…
Self-balancing pneumatic instrument mechanisms are very similar to…
Virtually any mass above absolute zero temperature emits…
A level switch is one detecting the level of liquid or solid (granules…
While the term “probability” may evoke images of…
Learning from reading printed text is a kind of problem-solving…
The Law of Continuity for fluids states that the product of mass…
The three “elementary” particles of matter comprising all…
In the United States, the ANSI and IEEE organizations have…
