Virtually any mass above absolute zero temperature emits…
Phasors are to AC circuit quantities as polarity is to DC circuit…
Feedback Control System Components Before we begin our discussion on…
DC electric motors generate torque by a reaction between two magnetic…
The purpose of a control valve actuator is to provide the motive force…
An electric motor is often used as a discrete control element in a…
The reason why a pneumatic control valve’s stem position…
A bridge circuit is basically a pair of voltage dividers where the…
Converting between disparate units of measurement is the bane of many…
One of the simplest classes of temperature sensor is one where…
An on/off valve is the fluid equivalent of an electrical switch: a…
One of the fundamental laws of electric circuits is Kirchhoff’s…
An important legacy technology for all kinds of continuous measurement…
A hand switch is exactly what the name implies: an electrical switch…
The simplest form of 4-20 mA current loop is the type used to…
Capacitors store energy in electric fields, proportional to the square…
A completely different way of measuring liquid level in vessels is to…
Calculus has a reputation for being difficult to learn, and with good…
The following animation shows the calculus concepts of differentiation…
Perhaps the most confusing aspect of discrete sensors is the…
When a high-energy photon strikes an atom, it may eject one of the…
Light has long been used as a long-range signaling medium. While…
A quantitative PID tuning procedure is a step-by-step approach leading…
Perhaps the most valuable skill an instrument technician can possess…
To review, voltage is the measure of potential energy available to…
In some process applications, it is important that the control valve…
Hydrogen ion activity in aqueous (water-solvent) solutions is a very…
pH is the measurement of the hydrogen ion activity in a liquid…
Valves can experience a number of problems, most of them either…
A pressure switch is one detecting the presence of fluid pressure.…
One of the most important accessories for any temperature-sensing…
Any power grid large enough to meet the demand of an entire nation…
(Will be addressed in future versions of this book)
A unique form of technical diagram for describing the abstract…
There are multiple motives for compromising the security of an…
The digital multimeter (DMM) is quite possibly the most useful tool in…
In November of 2007 a new computer virus was submitted to a virus…
Feedback obtained from industrial users of FF reveal a common pattern:…
The purpose of a control valve actuator is to provide the motive force…
Self-balancing mechanisms consisting solely of a baffle/nozzle…
Sensors used to measure vibration come in three basic types:…
Most of these formulae appear in molecular chemical form rather than…
Using filter cells to eliminate wavelengths associated with…
Cyber-security seems to have its own vocabulary, ranging from unwieldy…
A proximity switch is one detecting the proximity (closeness) of some…
So far we have just looked at instruments that sense, control, and…
Control valves are supposed to deliver reliable, repeatable control of…
By definition, a source is a device delivering energy into a system,…