So far we have just looked at instruments that sense, control, and influence process variables. Transmitters,…
Textbook
An important legacy technology for all kinds of continuous measurement is the self-balancing system. A…
Textbook
The following animation shows how a radio-energy pulse travels down and then up the waveguide of a guided-wave…
Textbook
Diagnostic ability is arguably the most difficult skill to develop within a student, and also the most…
Textbook
The two “process variables” we rely on most heavily in the field of electrical measurement and…
Textbook
Process measurements are often of an analog nature: the temperature of a furnace, the rate of fluid flow…
Textbook
RTDs are completely passive sensing elements, requiring the application of an externally-sourced electric…
Textbook
Sensors used to measure vibration come in three basic types: displacement, velocity, and acceleration.…
Textbook
In November of 2007 a new computer virus was submitted to a virus scanning service. The purpose of this new…
Textbook
Programmable logic controllers are essentially nothing more than special-purpose, industrial computers. As…
Textbook
A whole class of problem-solving techniques focuses on altering the given problem into a simpler form that is…
Textbook
The efficient identification and correction of instrument calibration errors is an important function for…
Textbook
Non-dispersive analysis, while newer in discovery than dispersive analysis (Isaac Newton’s 17th-century…
Textbook
A limitation inherent to pneumatic valve actuators is the amount of air flow required to or from the actuator…
Textbook
Self-balancing mechanisms consisting solely of a baffle/nozzle detector coupled to a feedback bellows, while…
Textbook
As we have seen, feedforward control is a way to improve the stability of a feedback control system in the…
Textbook
Volumes could be written about poor diagnostic technique. The following mistakes are not intended to comprise…
Textbook
Every programmable logic controller must have some means of receiving and interpreting signals from real-world…
Textbook
A pneumatic controller receives a process variable (PV) signal as a variable air pressure, compares that…
Textbook
Disturbances in the liquid tend to complicate liquid level measurement. These disturbances may result from…
Textbook
As we have seen, feedforward control is a way to improve the stability of a feedback control system in the…
Textbook
Imagine a liquid-level control system for a vessel, where the position of a level-sensing float directly sets…
Textbook
An engineer named Bob Metcalfe conceived the idea of Ethernet in 1973, while working for the Xerox research…
Textbook
As previously defined, calibration refers to the checking and adjustment of an instrument so that its output…
Textbook
A powerful mathematical concept useful for analyzing practically any physical system – electrical…
Textbook
The vast majority of modern process transmitters (both analog and digital) come equipped with a feature known…
Textbook
Disconnect Switches Disconnects are switches designed to isolate sections of a power system in case of damage…
Textbook
In a manually-controlled process, a human operator directly actuates some form of final control element…
Textbook
A chemical reaction resulting in a net release of energy is called exothermic. Conversely, a chemical reaction…
Textbook
Up until this point, we have explored various types of instrumentation diagram, each one making reference to…
Textbook
The disadvantages of pneumatic instruments are painfully evident to anyone familiar with both pneumatic and…
Textbook
Phasors are to AC circuit quantities as polarity is to DC circuit quantities: a way to express the…
Textbook
Circuit breakers used in residential, commercial, and light industrial service are self-tripping devices: they…
Textbook
One of the most important accessories for any temperature-sensing element is a pressure-tight sheath known as…
Textbook
As discussed at the beginning of this chapter, instrumentation safety may be broadly divided into two…
Textbook
A simple control system drawn in block diagram form looks like this: Information from the measuring device…
Textbook
A laser is a light source emitting waves of light that not only share the exact same frequency (color)…
Textbook
One of the fundamental laws of electric circuits is Kirchhoff’s Current Law, which states the algebraic…
Textbook
When a high-energy photon strikes an atom, it may eject one of the lower-level electrons from its shell,…
Textbook
A level switch is one detecting the level of liquid or solid (granules or powder) in a vessel. Level switches…
Textbook
Filled-bulb systems exploit the principle of fluid expansion to measure temperature. If a fluid is enclosed in…
Textbook
Abdelaziz, Ahmed (June 2014) Identified numerous typographical errors throughout the book, mostly repeated…
Textbook
Electromechanical relays may be connected together to perform logic and control functions, acting as logic…
Textbook
Since we often use electricity to convey energy from one location to another, it is important to be able to…
Textbook
Steam boilers are very common in industry, principally because steam power is so useful. Common uses for steam…
Textbook
A temperature switch is one detecting the temperature of some substance. Temperature switches often use…
Textbook
A fundamental principle in instrumentation system troubleshooting is that every instrument has at least one…
Textbook
Visualizing the actions of P, I, and D tuning parameters using graphs is extremely useful in predicting the…
Textbook
A limitation inherent to pneumatic valve actuators is the amount of air flow required to or from the actuator…
Textbook
To better understand the design and operation of self-balancing pneumatic mechanisms, it is helpful to examine…
Textbook
The following collection of photographs chronicles the complete disassembly of a Fisher E-body globe valve…
Textbook
Labwork is an essential part of any science-based curriculum. Here, much improvement may be made over the…
Textbook
The electrical conductivity of liquids is an important analytical measurement in many industrial processes.…
Textbook
Most pneumatic instruments use a simple but highly sensitive mechanism for converting mechanical motion into…
Textbook
The term “grid” refers to the conductors and equipment interconnecting power sources to power…
Textbook
A pressure switch is one that detects the presence of fluid pressure. Pressure switches often use diaphragms…
Textbook
In contrast to quantitative tuning procedures where definite numerical values for P, I, and D controller…
Textbook
In November of 2007 a new computer virus was submitted to a virus scanning service. The purpose of this new…
Textbook
Binary patterns are not just able to represent numerical values. Given a standardized code, they may represent…
Textbook
Atom: the smallest unit of matter that may be isolated by chemical means. Particle: a part of an atom,…
Textbook
Facebook
Google
GitHub
Linkedin