The vast majority of PID controllers in service today are digital in…
Constructing PID control systems using discrete components is a…
Valves can experience a number of problems, most of them either…
Hydrogen ion activity in aqueous (water-solvent) solutions is a very…
Diagnostic ability is arguably the most difficult skill to develop…
Although it seems each model of PLC has its own idiosyncratic standard…
Human-machine interfaces, or HMIs, are a critical part of nearly all…
As we have seen, the concept of integration is finding the…
Learning PLC programming is a very important skill. If your job…
The efficient identification and correction of instrument calibration…
Programmable logic controllers are essentially nothing more than…
As previously defined, calibration refers to the checking and…
The Law of Continuity for fluids states that the product of mass…
When control valves operate between fully open and fully shut, they…
“Polyphase” means “many phases,” describing a…
Phasors are to AC circuit quantities as polarity is to DC circuit…
As we have seen, feedforward control is a way to improve the stability…
A technological advance introduced in the late 1980’s was HART,…
The transformer is one of the most important components in all of AC…
Non-dispersive analysis, while newer in discovery than dispersive…
In November of 2007 a new computer virus was submitted to a virus…
An variable-area flowmeter is one where the fluid must pass through a…
Converting between disparate units of measurement is the bane of many…
The efficient identification and correction of instrument calibration…
A limitation inherent to pneumatic valve actuators is the amount of…
Multiple accessories exist for pressure-sensing devices to function…
A pneumatic controller receives a process variable (PV) signal as a…
Using filter cells to eliminate wavelengths associated with…
There are multiple motives for compromising the security of an…
So far we have just looked at instruments that sense, control, and…
Earlier in this chapter you were shown a model of a nitrogen atom with…
Modern DC and AC motor drives provide features useful when using…
A level switch is one detecting the level of liquid or solid (granules…
A flow switch is one detecting the flow of some fluid through a pipe.…
Hydrogen ion activity in aqueous (water-solvent) solutions is a very…
In order for any PID controller to be practical, it must be able to do…
Nearly every technical course teaches and tests students on…
Process analyzers measure the concentration of specific substances for…
Certain types of nuclear radiation easily penetrates the walls of…
Weight-based level instruments sense process level in a vessel by…
