Perhaps the most basic and necessary protective relay function is overcurrent: commanding a circuit breaker to…
Textbook
Disconnect Switches Disconnects are switches designed to isolate sections of a power system in case of damage…
Textbook
The digital multimeter (DMM) is quite possibly the most useful tool in the instrument technician’s…
Textbook
Creative Commons Attribution 4.0 International Public License By exercising the Licensed Rights (defined…
Textbook
There is much to be said for neatness of assembly in electrical signal wiring. Even though the electrons…
Textbook
In addition to directly performing logic functions, electromechanical relays may also be used as interposing…
Textbook
Any physical location in an industrial facility harboring the potential of explosion due to the presence of…
Textbook
An important type of “accessory” relay, especially for legacy electromechanical protective relays,…
Textbook
The reason why a pneumatic control valve’s stem position corresponds linearly to the amount of air…
Textbook
Regulating the electric power sent to an electric motor is a task performed by high-speed switching…
Textbook
There are several different methods useful for causing an AC induction motor to brake, or slow down: DC…
Textbook
All masses require force to accelerate (we can also think of this in terms of the mass generating a reaction…
Textbook
Disturbances in the liquid tend to complicate liquid level measurement. These disturbances may result from…
Textbook
A special type flowmeter suited for powdered or granular solids is the weighfeeder. One of the most common…
Textbook
A pneumatic controller receives a process variable (PV) signal as a variable air pressure, compares that…
Textbook
A pressure switch is one detecting the presence of fluid pressure. Pressure switches often use diaphragms or…
Textbook
Any power grid large enough to meet the demand of an entire nation must have multiple generators drawing from…
Textbook
The digital multimeter (DMM) is quite possibly the most useful tool in the instrument technician’s…
Textbook
In reliability engineering, it is important to be able to quantity the reliability (or conversely, the…
Textbook
Many traditional flowmeter technologies respond to the volumetric flow rate of the moving fluid.…
Textbook
Multiple accessories exist for pressure-sensing devices to function optimally in challenging process…
Textbook
An important legacy technology for all kinds of continuous measurement is the self-balancing system. A…
Textbook
The majority of flowmeter technologies operate on the principle of interpreting fluid flow based on the…
Textbook
One of the most important accessories for any temperature-sensing element is a pressure-tight sheath known as…
Textbook
A hand switch is exactly what the name implies: an electrical switch actuated by a person’s hand motion.…
Textbook
In a manually-controlled process, a human operator directly actuates some form of final control element…
Textbook
A level switch is one detecting the level of liquid or solid (granules or powder) in a vessel. Level switches…
Textbook
Any conductor possesses a characteristic called inductance: the ability to store energy in the form of a…
Textbook
Feedback Control System Components Before we begin our discussion on process control, we must define a few key…
Textbook
The vast majority of PID controllers in service today are digital in nature. Microprocessors executing PID…
Textbook
There are several different methods useful for causing an AC induction motor to brake, or slow down: DC…
Textbook
I remember first learning about the world-wide Internet, and wondering what it actually looked like. The first…
Textbook
Weight-based level instruments sense process level in a vessel by directly measuring the weight of the vessel.…
Textbook
Filled-bulb systems exploit the principle of fluid expansion to measure temperature. If a fluid is enclosed in…
Textbook
A special type flowmeter suited for powdered or granular solids is the weighfeeder. One of the most common…
Textbook
Solids tend to expand when heated. The amount that a solid sample will expand with increased temperature…
Textbook
This section does not describe a particular type of flowmeter, but rather a design that may be implemented for…
Textbook
There are several different methods useful for causing an AC induction motor to brake, or slow down: DC…
Textbook
The following animation shows the calculus concepts of differentiation and integration (with respect to time)…
Textbook
Lipták, Béla G. et al., Instrument Engineers’ Handbook – Process Measurement and Analysis Volume I,…
Textbook
Many years ago, when I was first learning about electricity, I happened to discover a length of coaxial…
Textbook
Perhaps the most important rule to obey when using pneumatic instruments is to maintain clean and dry…
Textbook
Some analyzers measure the composition of a process stream by directly immersing the sensing element in that…
Textbook
Take for instance the problem of measuring fluid flow through a pipe. To the layperson, this may seem to be a…
Textbook
A unique form of differential pressure-based flow measurement deserves its own section in this flow…
Textbook
A temperature switch is one detecting the temperature of some substance. Temperature switches often use…
Textbook
Phasors are to AC circuit quantities as polarity is to DC circuit quantities: a way to express the…
Textbook
There is much to be said for neatness of assembly in electrical signal wiring. Even though the electrons…
Textbook
By definition, a source is a device delivering energy into a system, while a load is a device extracting…
Textbook
Instrument technicians should not have to concern themselves over the programming details internal to digital…
Textbook
Using filter cells to eliminate wavelengths associated with interfering gases is called positive filtering in…
Textbook
AC induction motors are based on the principle of a rotating magnetic field produced by a set of stationary…
Textbook
Facebook
Google
GitHub
Linkedin