The key to understanding how three-phase electric motors work is to…
DC electric motors generate torque by a reaction between two magnetic…
An electric motor is often used as a discrete control element in a…
AC induction motors are based on the principle of a rotating magnetic…
There are several different methods useful for causing an AC induction…
The simplest form of 4-20 mA current loop is the type used to…
Regulating the electric power sent to an electric motor is a task…
A simple control system drawn in block diagram form looks like this:…
Modern DC and AC motor drives provide features useful when using…
The following animation shows how the “rotating” magnetic…
Modern DC and AC motor drives provide features useful when using…
The purpose of a control valve actuator is to provide the motive force…
Perhaps the most important rule of controller tuning is to know the…
The reason why a pneumatic control valve’s stem position…
Negative feedback systems, in general, tend to cause confusion for…
In addition to directly performing logic functions, electromechanical…
Although it seems each model of PLC has its own idiosyncratic standard…
Process measurements are often of an analog nature: the temperature of…
To better understand the design and operation of self-balancing…
There are several different methods useful for causing an AC induction…
A limit switch detects the physical motion of an object by direct…
The vast majority of PID controllers in service today are digital in…
DC electric motors generate torque by a reaction between two magnetic…
The simplest form of 4-20 mA current loop is the type used to…
The simple PLC ladder diagram (LD) commands consist of contacts and…
Non-dispersive analysis, while newer in discovery than dispersive…
A bridge circuit is basically a pair of voltage dividers where the…
In the United States, the most common language used to program PLCs is…
Virtually any mass above absolute zero temperature emits…
Perhaps the most basic and necessary protective relay function is…
An important type of “accessory” relay, especially for…
A whole class of problem-solving techniques focuses on altering the…
The reason why a pneumatic control valve’s stem position…
There are many process control applications in the industry where it…
One of the simplest classes of temperature sensor is one where…
PID control can be a confusing concept to understand. Here, a brief…
To better understand the design and operation of self-balancing…
A control strategy similar to ratio control is relation control. This…
In November of 2007 a new computer virus was submitted to a virus…
A temperature switch is one detecting the temperature of some…
Abdelaziz, Ahmed (June 2014) Identified numerous typographical errors…
The final step in treating wastewater before releasing it into the…
Much of our knowledge about atomic structure comes from experimental…
When control valves operate between fully open and fully shut, they…
By definition, a source is a device delivering energy into a system,…
As we have seen, the concept of integration is finding the…
A design-based fortification is one rooted in technical details of…
A pressure switch is one detecting the presence of fluid pressure.…
A hand switch is exactly what the name implies: an electrical switch…
The vast majority of modern process transmitters (both analog and…
