The simplest form of 4-20 mA current loop is the type used to…
Much has been written about the benefits of robust PID control.…
In order for any PID controller to be practical, it must be able to do…
In this section I will show screenshots from a process loop simulation…
A pneumatic controller receives a process variable (PV) signal as a…
I remember first learning about the world-wide Internet, and wondering…
Learning from reading printed text is a kind of problem-solving…
Human-machine interfaces, or HMIs, are a critical part of nearly all…
The concepts of calibration (trimming) and ranging are often difficult…
Filled-bulb systems exploit the principle of fluid expansion to…
Recall that an exothermic chemical reaction is one that releases a net…
Those familiar with industrial instrumentation will find much within…
Layer 1 of the OSI Reference Model is where we define the…
In reliability engineering, it is important to be able to quantity the…
Temperature measurement devices may be classified into two broad…
An variable-area flowmeter is one where the fluid must pass through a…
The final step in treating wastewater before releasing it into the…
Up until this point, we have explored various types of instrumentation…
An important performance parameter for transmitter instruments is…
As we have seen, feedforward control is a way to improve the stability…
An important legacy technology for all kinds of continuous measurement…
“As to methods there may be a million and then some, but…
Control valves are supposed to deliver reliable, repeatable control of…
A proximity switch is one detecting the proximity (closeness) of some…
Many years ago, when I was first learning about electricity, I…
The three “elementary” particles of matter comprising all…
The vast majority of modern process transmitters (both analog and…
A 4 to 20 mA current signal represents some signal along a 0 to 100…
In order for any PID controller to be practical, it must be able to do…
An electromechanical relay is an electrical switch actuated by an…
As defined previously, calibration means the comparison and adjustment…
Disturbances in the liquid tend to complicate liquid level…
Much of our knowledge about atomic structure comes from experimental…
A very simple device used to measure pressure is the manometer: a…
All masses require force to accelerate (we can also think of this in…
An interesting parallel to the “unity fraction” unit…
Tube, like pipe, is a hollow structure designed to provide an enclosed…
Human-machine interfaces, or HMIs, are a critical part of nearly all…
DC electric motors generate torque by a reaction between two magnetic…
This section does not describe a particular type of flowmeter, but…
“Polyphase” means “many phases,” describing a…
Perhaps the simplest form of solid or liquid level measurement is with…
Displacer level instruments exploit Archimedes’ Principle to…
Those familiar with industrial instrumentation will find much within…