Instantaneous and Time-overcurrent (50/51) Protection

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

---

Textbook

Proportional-only Offset

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

---

Textbook

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

Calibration Procedures in Linear, Non-Linear and Discrete Instruments

As described earlier in this chapter, calibration refers to the adjustment of an instrument so its output…

---

Textbook

Practical Topic Coverage

Nearly every technical course teaches and tests students on definitions, basic concepts, and at least some…

---

Textbook

FOUNDATION Fieldbus Function Blocks

Data-processing modules within FF systems are known as function blocks. Sometimes these blocks serve merely to…

---

Textbook

Zero and Span Adjustments (Analog Instruments)

Linearity of Measurement Instruments The purpose of calibration is to ensure the input and output of an…

---

Textbook

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

Measuring Electrical Conductivity

The electrical conductivity of liquids is an important analytical measurement in many industrial processes.…

---

Textbook

Transfer Function Analysis

An extremely important topic in engineering is that of transfer functions. Simply defined, a transfer function…

---

Textbook

Motives for Compromising the Security of an Industrial Control System

There are multiple motives for compromising the security of an industrial control system, some of which…

---

Textbook

Electrical Resistance and Ohm’s Law

To review, voltage is the measure of potential energy available to electric charges. Current is the uniform…

---

Textbook

Actuator Bench-set

Valve actuators provide force to move control valve trim. For precise positioning of a control valve, there…

---

Textbook

How to Teach Yourself PLC Programming

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

---

Textbook

Digital PID Controllers

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

---

Textbook

FOUNDATION Fieldbus Design Philosophy

To understand just how different FOUNDATION Fieldbus is from other digital instrument systems, consider a…

---

Textbook

Understanding the “Normal” Status of a Process Switch

Perhaps the most confusing aspect of discrete sensors is the definition of a sensor’s normal status.…

---

Textbook

Rotating Magnetic Fields in Three-phase AC Induction Motors

The following animation shows how the “rotating” magnetic field of a three-phase AC induction…

---

Textbook

Introduction to Calculus

Calculus. Few areas of mathematics are as powerfully useful in describing and analyzing the physical…

---

Textbook

On/off Shut-off Valves

An on/off valve is the fluid equivalent of an electrical switch: a device that either allows unimpeded flow or…

---

Textbook