Self-balancing pneumatic instrument mechanisms are very similar to negative-feedback operational amplifier…
Textbook
A level switch is one detecting the level of liquid or solid (granules or powder) in a vessel. Level switches…
Textbook
“Feedforward” is a rather under-used control strategy capable of managing a great many types of…
Textbook
This animation shows the basic operation of a gas chromatograph, showing the separation of different molecular…
Textbook
(Will be addressed in future versions of this book)
Textbook
Human-machine interfaces, or HMIs, are a critical part of nearly all control systems, complementing the…
Textbook
A bridge circuit is basically a pair of voltage dividers where the circuit output is taken as the difference…
Textbook
Measuring the flow rate of liquid through an open channel is not unlike measuring the flow rate of a liquid…
Textbook
Impedance in a series circuit is the orthogonal sum of resistance and reactance: \[Z = \sqrt{R^2 + (X_L -…
Textbook
Feedback Control System Components Before we begin our discussion on process control, we must define a few key…
Textbook
Capacitors store energy in electric fields, proportional to the square of voltage. Inductors store energy in…
Textbook
Volumes could be written about poor diagnostic technique. The following mistakes are not intended to comprise…
Textbook
A 4 to 20 mA current signal represents some signal along a 0 to 100 percent scale. Usually, this scale is…
Textbook
Creative Commons Attribution 4.0 International Public License By exercising the Licensed Rights (defined…
Textbook
Weight-based level instruments sense process level in a vessel by directly measuring the weight of the vessel.…
Textbook
Disconnect Switches Disconnects are switches designed to isolate sections of a power system in case of damage…
Textbook
A vertical column of fluid generates a pressure at the bottom of the column owing to the action of gravity on…
Textbook
The following animation shows how a radio-energy pulse travels down and then up the waveguide of a guided-wave…
Textbook
An variable-area flowmeter is one where the fluid must pass through a restriction whose area increases with…
Textbook
Perhaps the most basic and necessary protective relay function is overcurrent: commanding a circuit breaker to…
Textbook
Electrical Resistance Resistance (\(R\)) is the dissipative opposition to an electric current, analogous to…
Textbook
Lipták, Béla G. et al., Instrument Engineers’ Handbook – Process Measurement and Analysis Volume I,…
Textbook
Given the ability of pressurized fluids to transmit force over long distances, it is not surprising that many…
Textbook
Fluid pressure exerts force on any surface area it contacts, as described by the formula \(F = PA\). One…
Textbook
A proximity switch is one detecting the proximity (closeness) of some object. By definition, these switches…
Textbook
Suppose we wished to measure the rate of propane gas flow through a hose to a torch: Flowmeters appropriate…
Textbook
“Feedforward” is a rather under-used control strategy capable of managing a great many types of…
Textbook
DC electric current signals may also be used to communicate process measurement information from transmitters…
Textbook
Those familiar with industrial instrumentation will find much within the electric power industry remarkably…
Textbook
Sometimes we encounter a diversity of instrument signal standards in one control system. Such is the case with…
Textbook
An variable-area flowmeter is one where the fluid must pass through a restriction whose area increases with…
Textbook
As we have seen, feedforward control is a way to improve the stability of a feedback control system in the…
Textbook
Labwork is an essential part of any science-based curriculum. Here, much improvement may be made over the…
Textbook
Textbook
“Polyphase” means “many phases,” describing a form of AC electrical system where…
Textbook
Earlier in this chapter you were shown a model of a nitrogen atom with a dense nucleus (comprised of protons…
Textbook
Displacer level instruments exploit Archimedes’ Principle to detect liquid level by continuously…
Textbook
One of the simplest classes of temperature sensor is one where temperature effects a change in electrical…
Textbook
In this section I will show screenshots from a process loop simulation program illustrating the effectiveness…
Textbook
Regulating the electric power sent to an electric motor is a task performed by high-speed switching…
Textbook
Facebook
Google
GitHub
Linkedin