Educational Resources

Categories

Basic Feedback Control Principles

Basic Feedback Control Principles

Feedback Control System Components Before we begin our discussion on process control, we must define a few key…


Textbook

Safety Instrumented Functions and Systems

Safety Instrumented Functions and Systems

A Safety Instrumented Function, or SIF, is one or more components designed to execute a specific…


Textbook

Wastewater Disinfection Example

Wastewater Disinfection Example

The final step in treating wastewater before releasing it into the natural environment is to kill any harmful…


Textbook

Energy in Chemical Reactions

Energy in Chemical Reactions

A chemical reaction resulting in a net release of energy is called exothermic. Conversely, a chemical reaction…


Textbook

Chemical Reactor Temperature Control Example

Chemical Reactor Temperature Control Example

Sometimes we encounter a diversity of instrument signal standards in one control system. Such is the case with…


Textbook

Analytical Measurements of Chemical Compositions

Analytical Measurements of Chemical Compositions

A great many chemical composition measurements may be made indirectly by means of electricity, if those…


Textbook

Feedforward with Dynamic Compensation

Feedforward with Dynamic Compensation

As we have seen, feedforward control is a way to improve the stability of a feedback control system in the…


Textbook

Atomic Theory and Chemical Symbols

Atomic Theory and Chemical Symbols

The three “elementary” particles of matter comprising all atoms are electrons, protons, and…


Textbook

Safety Gas Analyzers

Safety Gas Analyzers

Process analyzers measure the concentration of specific substances for the purpose of measuring and/or…


Textbook

Formulae for Common Chemical Compounds

Formulae for Common Chemical Compounds

Most of these formulae appear in molecular chemical form rather than structural form. For example, ethanol…


Textbook

Colorimetric and Potentiometric pH Measurement

Colorimetric and Potentiometric pH Measurement

pH is the measurement of the hydrogen ion activity in a liquid solution. It is one of the most common forms of…


Textbook

Instrument Turndown (Rangedown)

Instrument Turndown (Rangedown)

An important performance parameter for transmitter instruments is something often referred to as turndown or…


Textbook

Differential Pressure Transmitters

Differential Pressure Transmitters

One of the most common, and most useful, pressure measuring instruments in industry is the differential…


Textbook

Digital PID Controllers

Digital PID Controllers

The vast majority of PID controllers in service today are digital in nature. Microprocessors executing PID…


Textbook

A Comparison of PID Controller Tuning Techniques

A Comparison of PID Controller Tuning Techniques

In this section I will show screenshots from a process loop simulation program illustrating the effectiveness…


Textbook

Fundamental Principles of Industrial Instrumentation

Fundamental Principles of Industrial Instrumentation

Shown here is a partial listing of principles applied in the subject matter of this chapter, given for the…


Textbook

Circuit Breakers and Disconnects

Circuit Breakers and Disconnects

Disconnect Switches Disconnects are switches designed to isolate sections of a power system in case of damage…


Textbook

Instantaneous and Time-overcurrent (50/51) Protection

Instantaneous and Time-overcurrent (50/51) Protection

Perhaps the most basic and necessary protective relay function is overcurrent: commanding a circuit breaker to…


Textbook

Root Mean Square (RMS) Quantities

Root Mean Square (RMS) Quantities

It is often useful to express the amplitude of an alternating quantity such as voltage or current in terms…


Textbook

Weighfeeders

Weighfeeders

A special type flowmeter suited for powdered or granular solids is the weighfeeder. One of the most common…


Textbook

Phasor Analysis of Transformer Circuits

Phasor Analysis of Transformer Circuits

Three-phase AC is the dominant mode of electric power generation and distribution in modern societies.…


Textbook

Applications of Spectroscopy for Analytical Measurement

Applications of Spectroscopy for Analytical Measurement

Much of our knowledge about atomic structure comes from experimental data relating the interaction between…


Textbook

Derivative (Rate) Control

Derivative (Rate) Control

The final element of PID control is the “D” term, which stands for derivative. This is a calculus…


Textbook

Chemiluminescence Measurement

Chemiluminescence Measurement

Recall that an exothermic chemical reaction is one that releases a net sum of energy, as opposed to an…


Textbook

Material Volume Measurement

Material Volume Measurement

A variety of technologies exist to measure the quantity of stored material in a vessel. For liquid…


Textbook

4 to 20 mA Analog Current Signals

4 to 20 mA Analog Current Signals

The most popular form of signal transmission used in modern industrial instrumentation systems (as of this…


Textbook

Function Block Diagram (FBD) Programming

Function Block Diagram (FBD) Programming

(Will be addressed in future versions of this book)


Textbook

Practical PID Controller Features

Practical PID Controller Features

In order for any PID controller to be practical, it must be able to do more than just implement the PID…


Textbook

Analog Signal Conditioning and Referencing

Analog Signal Conditioning and Referencing

Modern analog-to-digital converters are phenomenally accurate, dependable, repeatable, and surprisingly…


Textbook

How to Teach Yourself PLC Programming

How to Teach Yourself PLC Programming

Learning PLC programming is a very important skill. If your job involves programming, then you will likely…


Textbook

Elementary Thermodynamics

Elementary Thermodynamics

Thermodynamics is the study of heat, temperature, and their related effects in physical systems. As a subject,…


Textbook

Kirchhoff’s Current and Voltage Laws

Kirchhoff’s Current and Voltage Laws

Two extremely important principles in electric circuits were codified by Gustav Robert Kirchhoff in the year…


Textbook

Basics of pH Measurement in Industrial Control

Basics of pH Measurement in Industrial Control

Hydrogen ion activity in aqueous (water-solvent) solutions is a very important parameter for a wide variety of…


Textbook

Proximity Switches

Proximity Switches

A proximity switch is one detecting the proximity (closeness) of some object. By definition, these switches…


Textbook

Understanding the Calculus Concepts of Differentiation and Integration

Understanding the Calculus Concepts of Differentiation and Integration

The following animation shows the calculus concepts of differentiation and integration (with respect to time)…


Textbook

Applications of Spectroscopy for Analytical Measurement

Applications of Spectroscopy for Analytical Measurement

Much of our knowledge about atomic structure comes from experimental data relating the interaction between…


Textbook

ANSI/IEEE Function Number Codes

ANSI/IEEE Function Number Codes

In the United States, the ANSI and IEEE organizations have standardized a set of numerical codes referring to…


Textbook

Proportional-only Offset

Proportional-only Offset

A fundamental limitation of proportional control has to do with its response to changes in setpoint and…


Textbook

Classical Mechanics

Classical Mechanics

Classical mechanics (often called Newtonian mechanics in honor of Isaac Newton) deal with forces and motions…


Textbook

Industrial Instrumentation Summary for Teachers

Industrial Instrumentation Summary for Teachers

To summarize some of the key points and concepts for teaching: Do not waste class time transmitting facts to…


Textbook

Digital PID Controllers

Digital PID Controllers

The vast majority of PID controllers in service today are digital in nature. Microprocessors executing PID…


Textbook

Assessing Student Learning

Assessing Student Learning

As a general rule, high achievement only takes place in an atmosphere of high expectations. Sometimes these…


Textbook

Force-balance Pressure Transmitters

Force-balance Pressure Transmitters

An important legacy technology for all kinds of continuous measurement is the self-balancing system. A…


Textbook

Weighfeeders

Weighfeeders

A special type flowmeter suited for powdered or granular solids is the weighfeeder. One of the most common…


Textbook

Control Valve Characterization

Control Valve Characterization

Control valves are supposed to deliver reliable, repeatable control of process fluid flow rate over a wide…


Textbook

Controller Output Current Loops

Controller Output Current Loops

The simplest form of 4-20 mA current loop is the type used to represent the output of a process controller,…


Textbook

DC Motor Speed Control

DC Motor Speed Control

DC electric motors generate torque by a reaction between two magnetic fields: one field established by…


Textbook

Material Volume Measurement

Material Volume Measurement

A variety of technologies exist to measure the quantity of stored material in a vessel. For liquid…


Textbook

Phasor Analysis of Transformer Circuits

Phasor Analysis of Transformer Circuits

Three-phase AC is the dominant mode of electric power generation and distribution in modern societies.…


Textbook

Flow Measurement in Open Channels

Flow Measurement in Open Channels

Measuring the flow rate of liquid through an open channel is not unlike measuring the flow rate of a liquid…


Textbook

Vibration Sensors

Vibration Sensors

Sensors used to measure vibration come in three basic types: displacement, velocity, and acceleration.…


Textbook