A level switch is one detecting the level of liquid or solid (granules or powder) in a vessel. Level switches…
Textbook
Finally, we arrive at the loop diagram (sometimes called a loop sheet) for the compressor surge control system…
Textbook
Control strategies such as cascade, ratio, feedforward, and those containing limit and selector functions can…
Textbook
Every programmable logic controller must have some means of receiving and interpreting signals from real-world…
Textbook
All masses require force to accelerate (we can also think of this in terms of the mass generating a reaction…
Textbook
Filled-bulb systems exploit the principle of fluid expansion to measure temperature. If a fluid is enclosed in…
Textbook
A number of different sensors used in instrumentation generate DC voltage signals proportional to the process…
Textbook
A very common form of on/off valve used for pneumatic and hydraulic systems alike is the solenoid valve. A…
Textbook
A great many chemical composition measurements may be made indirectly by means of electricity, if those…
Textbook
It is often useful to express the amplitude of an alternating quantity such as voltage or current in terms…
Textbook
In some process applications, it is important that the control valve be able to completely stop fluid flow…
Textbook
The digital multimeter (DMM) is quite possibly the most useful tool in the instrument technician’s…
Textbook
Most pneumatic instruments use a simple but highly sensitive mechanism for converting mechanical motion into…
Textbook
By definition, a source is a device delivering energy into a system, while a load is a device extracting…
Textbook
As we have seen, the concept of integration is finding the accumulation of one variable multiplied by another…
Textbook
As we have seen, the concept of differentiation is finding the rate-of-change of one variable compared to…
Textbook
Given the ability of pressurized fluids to transmit force over long distances, it is not surprising that many…
Textbook
Capacitance Any two electrical conductors separated by an insulating medium possess the characteristic called…
Textbook
As previously defined, calibration refers to the checking and adjustment of an instrument so that its output…
Textbook
Pipe is a hollow structure designed to provide an enclosed pathway for fluids to flow, usually manufactured…
Textbook
As discussed at the beginning of this chapter, instrumentation safety may be broadly divided into two…
Textbook
A sliding-stem valve body is one where the moving parts slide with a linear motion. Some examples of…
Textbook
In a manually-controlled process, a human operator directly actuates some form of final control element…
Textbook
One of the fundamental laws of electric circuits is Kirchhoff’s Current Law, which states the algebraic…
Textbook
A level switch is one detecting the level of liquid or solid (granules or powder) in a vessel. Level switches…
Textbook
As described earlier in this chapter, calibration refers to the adjustment of an instrument so its output…
Textbook
The simple PLC ladder diagram (LD) commands consist of contacts and coils, arranged in sequences that mimic…
Textbook
Programmable logic controllers are essentially nothing more than special-purpose, industrial computers. As…
Textbook
A vertical column of fluid generates a pressure at the bottom of the column owing to the action of gravity on…
Textbook
Perhaps the most basic and necessary protective relay function is overcurrent: commanding a circuit breaker to…
Textbook
So far we have just looked at instruments that sense, control, and influence process variables. Transmitters,…
Textbook
Current is the name we give to the motion of electric charges from a point of high potential to a point of low…
Textbook
The vast majority of modern process transmitters (both analog and digital) come equipped with a feature known…
Textbook
Instrument technicians should not have to concern themselves over the programming details internal to digital…
Textbook
A wise PLC programmer once told me that the first thing any aspiring programmer should learn about the PLC…
Textbook
AC induction motors are based on the principle of a rotating magnetic field produced by a set of stationary…
Textbook
Electrical Resistance Resistance (\(R\)) is the dissipative opposition to an electric current, analogous to…
Textbook
Although analog electronic process controllers are considered a newer technology than pneumatic process…
Textbook
In order to provide an interface between the internal (digital) world of a computer and the external (analog)…
Textbook
Valve actuators provide force to move control valve trim. For precise positioning of a control valve, there…
Textbook
To review, voltage is the measure of potential energy available to electric charges. Current is the uniform…
Textbook
Regulating the electric power sent to an electric motor is a task performed by high-speed switching…
Textbook
In a manually-controlled process, a human operator directly actuates some form of final control element…
Textbook
Feedback obtained from industrial users of FF reveal a common pattern: Fieldbus is a powerful and reliable…
Textbook
DC electric current signals may also be used to communicate process measurement information from transmitters…
Textbook
Perhaps the most important rule to obey when using pneumatic instruments is to maintain clean and dry…
Textbook
Creative Commons Attribution 4.0 International Public License By exercising the Licensed Rights (defined…
Textbook
Learning how to tune PID controllers is a skill born of much practice. Regardless of how thoroughly you may…
Textbook
Coy, John J. et. al. (December 2012) Sampled graphic illustrations from his NASA Reference Publication…
Textbook
Converting between disparate units of measurement is the bane of many science students. The problem is worse…
Textbook
Some analyzers measure the composition of a process stream by directly immersing the sensing element in that…
Textbook
A form of protection against faults on long-distance power lines is called distance relaying, so named because…
Textbook
Volumes could be written about poor diagnostic technique. The following mistakes are not intended to comprise…
Textbook
In some process applications, it is important that the control valve be able to completely stop fluid flow…
Textbook
As previously defined, calibration refers to the checking and adjustment of an instrument so that its output…
Textbook
(Will be addressed in future versions of this book)
Textbook
Perhaps the simplest form of solid or liquid level measurement is with a float: a device that rides on the…
Textbook
Imagine a major marathon race, where hundreds of runners gather in one place to compete. When the starting gun…
Textbook
One of the simplest classes of temperature sensor is one where temperature effects a change in electrical…
Textbook
A quantitative PID tuning procedure is a step-by-step approach leading directly to a set of numerical values…
Textbook
Facebook
Google
GitHub
Linkedin