By definition, a source is a device delivering energy into a system,…
Circuit breakers used in residential, commercial, and light industrial…
While 50 and 51 (instantaneous and time overcurrent) relay functions…
Electrical power grids primarily consist of three-phase AC circuits.…
DC electric motors generate torque by a reaction between two magnetic…
A form of protection against faults on long-distance power lines is…
Since we often use electricity to convey energy from one location to…
One of the fundamental laws of electric circuits is Kirchhoff’s…
Current is the name we give to the motion of electric charges from a…
“Polyphase” means “many phases,” describing a…
Classical mechanics (often called Newtonian mechanics in honor of…
Circuit breakers are the “final control elements” of the…
In the United States, the ANSI and IEEE organizations have…
The term “grid” refers to the conductors and equipment…
The two “process variables” we rely on most heavily in the…
A machine in the broad sense of the word is any device designed to…
Three-phase AC is the dominant mode of electric power generation and…
Those familiar with industrial instrumentation will find much within…
Sometimes we encounter a diversity of instrument signal standards in…
The transformer is one of the most important components in all of AC…
An variable-area flowmeter is one where the fluid must pass through a…
Current is the name we give to the motion of electric charges from a…
The following animation shows how a radio-energy pulse travels down…
The vast majority of PID controllers in service today are digital in…
One of the marks of a successful problem-solver is a habit of applying…
The following animation shows the calculus concepts of differentiation…
Modern analog-to-digital converters are phenomenally accurate,…
As described earlier in this chapter, calibration refers to the…
One very convenient feature of waves is that their properties are…
The following animation shows a rotating phasor in three-dimensional…
A variety of technologies exist to measure the quantity of stored…
The digital multimeter (DMM) is quite possibly the most useful tool in…
Thermodynamics is the study of heat, temperature, and their related…
Sample sizes of chemical substances are often measured in moles. One…
This animation shows the basic operation of a gas chromatograph,…
The dispersion of visible light into its constituent colors goes all…
There is much to be said for neatness of assembly in electrical signal…
The following animation shows how the “rotating” magnetic…
The reason why a pneumatic control valve’s stem position…
Finally, we arrive at the loop diagram (sometimes called a loop sheet)…
A great many precision instruments use the principle of balance to…
The dispersion of visible light into its constituent colors goes all…
As we have seen, feedforward control is a way to improve the stability…
A very simple device used to measure pressure is the manometer: a…
Level gauges are perhaps the simplest indicating instrument for liquid…
The very purpose of physics is to quantitatively describe and explain…
A damper (otherwise known as a louvre) is a multi-element flow control…
A level switch is one detecting the level of liquid or solid (granules…
A completely different way of measuring liquid level in vessels is to…
Sometimes we encounter a diversity of instrument signal standards in…
A unique form of differential pressure-based flow measurement deserves…
As a general rule, high achievement only takes place in an atmosphere…
To show a practical process example, let’s examine three…
The key to understanding how three-phase electric motors work is to…
The simplest form of 4-20 mA current loop is the type used to…
Converting between disparate units of measurement is the bane of many…
The following animation shows how a radio-energy pulse travels down…
There are many process control applications in the industry where it…
A laser is a light source emitting waves of light that not only…
A very common form of on/off valve used for pneumatic and hydraulic…
