While 50 and 51 (instantaneous and time overcurrent) relay functions…
In the United States, the ANSI and IEEE organizations have…
By definition, a source is a device delivering energy into a system,…
The two “process variables” we rely on most heavily in the…
Disconnect Switches Disconnects are switches designed to isolate…
Current is the name we give to the motion of electric charges from a…
The term “grid” refers to the conductors and equipment…
Those familiar with industrial instrumentation will find much within…
Electrical power grids primarily consist of three-phase AC circuits.…
A form of protection against faults on long-distance power lines is…
Circuit breakers used in residential, commercial, and light industrial…
Since we often use electricity to convey energy from one location to…
“Polyphase” means “many phases,” describing a…
Three-phase AC is the dominant mode of electric power generation and…
One of the fundamental laws of electric circuits is Kirchhoff’s…
The transformer is one of the most important components in all of AC…
Learning from reading printed text is a kind of problem-solving…
As a general rule, high achievement only takes place in an atmosphere…
A fluid is any substance having the ability to flow: to freely change…
Sensors used to measure vibration come in three basic types:…
Filled-bulb systems exploit the principle of fluid expansion to…
A bridge circuit is basically a pair of voltage dividers where the…
DC electric current signals may also be used to communicate process…
The next level of detail is the Process and Instrument Diagram, or…
The simple PLC ladder diagram (LD) commands consist of contacts and…
Imagine a major marathon race, where hundreds of runners gather in one…
“Feedforward” is a rather under-used control strategy…
A limitation inherent to pneumatic valve actuators is the amount of…
Most of these formulae appear in molecular chemical form rather than…
As we have seen, the concept of integration is finding the…
A completely different way of measuring liquid level in vessels is to…
This animation shows the basic operation of a gas chromatograph,…
A very common form of on/off valve used for pneumatic and hydraulic…
I remember first learning about the world-wide Internet, and wondering…
Imagine a liquid-level control system for a vessel, where the position…
Creative Commons Attribution 4.0 International Public License By…
