DC electric motors generate torque by a reaction between two magnetic fields: one field established by…
Textbook
A bridge circuit is basically a pair of voltage dividers where the circuit output is taken as the difference…
Textbook
Electrical power grids primarily consist of three-phase AC circuits. This means most power lines (transmission…
Textbook
At the next OSI Reference Model layer (layer 4) is a set of protocols specifying how reliable communication…
Textbook
Control strategies such as cascade, ratio, feedforward, and those containing limit and selector functions can…
Textbook
Solids tend to expand when heated. The amount that a solid sample will expand with increased temperature…
Textbook
Light has long been used as a long-range signaling medium. While communication by light through open air is…
Textbook
This section does not describe a particular type of flowmeter, but rather a design that may be implemented for…
Textbook
A laser is a light source emitting waves of light that not only share the exact same frequency (color)…
Textbook
When control valves operate between fully open and fully shut, they serve much the same purpose in process…
Textbook
There are multiple motives for compromising the security of an industrial control system, some of which…
Textbook
While 50 and 51 (instantaneous and time overcurrent) relay functions monitor line current magnitude and guard…
Textbook
Any power grid large enough to meet the demand of an entire nation must have multiple generators drawing from…
Textbook
What is Calibration? To calibrate an instrument means to check and adjust (if necessary) its response so the…
Textbook
The final element of PID control is the “D” term, which stands for derivative. This is a calculus…
Textbook
Several different technologies exist for the conversion of fluid pressure into an electrical signal response.…
Textbook
Modern DC and AC motor drives provide features useful when using electric motors as final control elements.…
Textbook
Suppose we wished to measure the consumption of propane over time for a large propane storage tank supplying a…
Textbook
Although it seems each model of PLC has its own idiosyncratic standard for programming, there does exist an…
Textbook
In a manually-controlled process, a human operator directly actuates some form of final control element…
Textbook