The following photograph shows a large air blower in a wastewater…
Human-machine interfaces, or HMIs, are a critical part of nearly all…
A 4 to 20 mA current signal represents some signal along a 0 to 100…
These fortifications focus on human behavior rather than system design…
Labwork is an essential part of any science-based curriculum. Here,…
Another category of control strategies involves the use of signal…
So far we have just looked at instruments that sense, control, and…
In addition to directly performing logic functions, electromechanical…
Although it seems each model of PLC has its own idiosyncratic standard…
A wise PLC programmer once told me that the first thing any aspiring…
In order to provide an interface between the internal (digital) world…
One of the most important accessories for any temperature-sensing…
Volumes could be written about poor diagnostic technique. The…
Modern DC and AC motor drives provide features useful when using…
Multiple accessories exist for pressure-sensing devices to function…
The vast majority of PID controllers in service today are digital in…
PID control can be a confusing concept to understand. Here, a brief…
Steam boilers are very common in industry, principally because steam…
There are multiple motives for compromising the security of an…
Programmable logic controllers are essentially nothing more than…
Certain types of nuclear radiation easily penetrates the walls of…
The Law of Mass Conservation states that matter can neither be created…
An on/off valve is the fluid equivalent of an electrical switch: a…
As defined previously, calibration means the comparison and adjustment…
It is often useful to express the amplitude of an alternating quantity…
A design-based fortification is one rooted in technical details of…
Using filter cells to eliminate wavelengths associated with…
Nearly every technical course teaches and tests students on…
Modern analog-to-digital converters are phenomenally accurate,…
In the United States, the most common language used to program PLCs is…
Another category of control strategies involves the use of signal…
One of the most important accessories for any temperature-sensing…
There are many process control applications in the industry where it…
An engineer named Bob Metcalfe conceived the idea of Ethernet in 1973,…
Creative Commons Attribution 4.0 International Public License By…
Virtually any mass above absolute zero temperature emits…
A very simple device used to measure pressure is the manometer: a…
Every programmable logic controller must have some means of receiving…
All masses require force to accelerate (we can also think of this in…
Temperature measurement devices may be classified into two broad…
Learning from reading printed text is a kind of problem-solving…
In contrast to quantitative tuning procedures where definite numerical…
As we have seen, feedforward control is a way to improve the stability…
Disconnect Switches Disconnects are switches designed to isolate…
Electromechanical relays may be connected together to perform logic…
Imagine a liquid-level control system for a vessel, where the position…
To show a practical process example, let’s examine three…
A special type flowmeter suited for powdered or granular solids is the…
One of the great benefits of digital technology is the ability to…
A number of different sensors used in instrumentation generate DC…
Valves can experience a number of problems, most of them either…
Stoichiometry is the accounting of atoms before and after a chemical…
These fortifications focus on human behavior rather than system design…
Linearity of Measurement Instruments The purpose of calibration is to…
First, let us review some of the properties of differentials and…
Coy, John J. et. al. (December 2012) Sampled graphic illustrations…
A unique form of technical diagram for describing the abstract…
Since we often use electricity to convey energy from one location to…
While the term “probability” may evoke images of…
Those familiar with industrial instrumentation will find much within…
