Instrument technicians should not have to concern themselves over the…
“Polyphase” means “many phases,” describing a…
The vast majority of PID controllers in service today are digital in…
Data-processing modules within FF systems are known as function…
Hydrogen ion activity in aqueous (water-solvent) solutions is a very…
The simple PLC ladder diagram (LD) commands consist of contacts and…
Constructing PID control systems using discrete components is a…
The two “process variables” we rely on most heavily in the…
As previously defined, calibration refers to the checking and…
Valves can experience a number of problems, most of them either…
A completely different way of measuring liquid level in vessels is to…
Human-machine interfaces, or HMIs, are a critical part of nearly all…
The Law of Continuity for fluids states that the product of mass…
Although it seems each model of PLC has its own idiosyncratic standard…
Light is known to interact with matter in very specific ways, which…
As discussed at the beginning of this chapter, instrumentation safety…
RTDs are completely passive sensing elements, requiring the…
In the United States, the most common language used to program PLCs is…
As we have seen, feedforward control is a way to improve the stability…
Diagnostic ability is arguably the most difficult skill to develop…
Control valves are supposed to deliver reliable, repeatable control of…
An electric motor is often used as a discrete control element in a…
Feedback Control System Components Before we begin our discussion on…
By definition, a source is a device delivering energy into a system,…
Linearity of Measurement Instruments The purpose of calibration is to…
Learning PLC programming is a very important skill. If your job…
Feedback obtained from industrial users of FF reveal a common pattern:…
Suppose we wished to measure the rate of propane gas flow through a…
Creative Commons Attribution 4.0 International Public License By…
In November of 2007 a new computer virus was submitted to a virus…
Electrical power grids primarily consist of three-phase AC circuits.…
An electromechanical relay is an electrical switch actuated by an…
A very common method for directly controlling low flow rates of fluids…
A temperature switch is one detecting the temperature of some…
Human-machine interfaces, or HMIs, are a critical part of nearly all…
Every programmable logic controller must have some means of receiving…
The digital multimeter (DMM) is quite possibly the most useful tool in…
Regulating the electric power sent to an electric motor is a task…
Any physical location in an industrial facility harboring the…
Process measurements are often of an analog nature: the temperature of…