As discussed at the beginning of this chapter, instrumentation safety may be broadly divided into two…
Textbook
“Feedforward” is a rather under-used control strategy capable of managing a great many types of…
Textbook
PID control can be a confusing concept to understand. Here, a brief summary of each term within PID (P. I, and…
Textbook
Learning PLC programming is a very important skill. If your job involves programming, then you will likely…
Textbook
Every programmable logic controller must have some means of receiving and interpreting signals from real-world…
Textbook
Labwork is an essential part of any science-based curriculum. Here, much improvement may be made over the…
Textbook
Modern analog-to-digital converters are phenomenally accurate, dependable, repeatable, and surprisingly…
Textbook
Perhaps the most confusing aspect of discrete sensors is the definition of a sensor’s normal status.…
Textbook
Fieldbus devices require far more attention in their initial setup and commissioning than their analog…
Textbook
The following photograph shows a large air blower in a wastewater treatment facility equipped with a…
Textbook
In order to provide an interface between the internal (digital) world of a computer and the external (analog)…
Textbook
(Will be addressed in future versions of this book)
Textbook
While the term “probability” may evoke images of imprecision, probability is in fact an exact…
Textbook
There are multiple motives for compromising the security of an industrial control system, some of which…
Textbook
The purpose of a control valve actuator is to provide the motive force to operate a valve mechanism. Both…
Textbook
The simple PLC ladder diagram (LD) commands consist of contacts and coils, arranged in sequences that mimic…
Textbook
Data-processing modules within FF systems are known as function blocks. Sometimes these blocks serve merely to…
Textbook
A technological advance introduced in the late 1980’s was HART, an acronym standing for Highway…
Textbook
A simple control system drawn in block diagram form looks like this: Information from the measuring device…
Textbook
Disturbances in the liquid tend to complicate liquid level measurement. These disturbances may result from…
Textbook
Temperature measurement devices may be classified into two broad types: contact and non-contact. Contact-type…
Textbook
Process analyzers measure the concentration of specific substances for the purpose of measuring and/or…
Textbook
The very purpose of physics is to quantitatively describe and explain the physical world in as few terms as…
Textbook
Fluid pressure exerts force on any surface area it contacts, as described by the formula \(F = PA\). One…
Textbook
A damper (otherwise known as a louvre) is a multi-element flow control device generally used to throttle large…
Textbook
The advent of “smart” field instruments containing microprocessors has been a great advance for…
Textbook
Sample sizes of chemical substances are often measured in moles. One mole of a substance is defined as a…
Textbook
A quantitative PID tuning procedure is a step-by-step approach leading directly to a set of numerical values…
Textbook
Regulating the electric power sent to an electric motor is a task performed by high-speed switching…
Textbook
An important performance parameter for transmitter instruments is something often referred to as turndown or…
Textbook
A different strategy for controlling the flow of fluid is to insert a rotary element into the flow path.…
Textbook
An variable-area flowmeter is one where the fluid must pass through a restriction whose area increases with…
Textbook
AC induction motors are based on the principle of a rotating magnetic field produced by a set of stationary…
Textbook
The following animation shows how a radio-energy pulse travels down and then up the waveguide of a guided-wave…
Textbook
An interesting parallel to the “unity fraction” unit conversion technique is something referred to…
Textbook
A fluid is any substance having the ability to flow: to freely change shape and move under the influence of a…
Textbook
A sliding-stem valve body is one where the moving parts slide with a linear motion. Some examples of…
Textbook
A completely different way of measuring liquid level in vessels is to bounce a traveling wave off the surface…
Textbook
Binary patterns are not just able to represent numerical values. Given a standardized code, they may represent…
Textbook
Light is known to interact with matter in very specific ways, which may be exploited as a means of measuring…
Textbook
Learning from reading printed text is a kind of problem-solving activity it is own right. The problem is how…
Textbook
Many liquid substances undergo a process whereby their constituent molecules split into positively and…
Textbook
Circuit breakers used in residential, commercial, and light industrial service are self-tripping devices: they…
Textbook
Stoichiometry is the accounting of atoms before and after a chemical reaction. It is an expression of the Law…
Textbook
The following animation shows how the “rotating” magnetic field of a three-phase AC induction…
Textbook
Any physical location in an industrial facility harboring the potential of explosion due to the presence of…
Textbook
RTDs are completely passive sensing elements, requiring the application of an externally-sourced electric…
Textbook
An important design parameter of a control valve is the position it will “fail” to if it loses…
Textbook
As previously defined, calibration refers to the checking and adjustment of an instrument so that its output…
Textbook
While 50 and 51 (instantaneous and time overcurrent) relay functions monitor line current magnitude and guard…
Textbook
The reason why a pneumatic control valve’s stem position corresponds linearly to the amount of air…
Textbook
A flow switch is one detecting the flow of some fluid through a pipe. Flow switches often use…
Textbook
By definition, a source is a device delivering energy into a system, while a load is a device extracting…
Textbook
As described earlier in this chapter, calibration refers to the adjustment of an instrument so its output…
Textbook
When a high-energy photon strikes an atom, it may eject one of the lower-level electrons from its shell,…
Textbook
Capacitors store energy in electric fields, proportional to the square of voltage. Inductors store energy in…
Textbook
To understand just how different FOUNDATION Fieldbus is from other digital instrument systems, consider a…
Textbook
Nearly every technical course teaches and tests students on definitions, basic concepts, and at least some…
Textbook
The Law of Mass Conservation states that matter can neither be created nor destroyed. The Law of Energy…
Textbook
Process analyzers measure the concentration of specific substances for the purpose of measuring and/or…
Textbook
Facebook
Google
GitHub
Linkedin