This section shows some of the many instrument symbols found in…
The final step in treating wastewater before releasing it into the…
Much has been written about the benefits of robust PID control.…
A pressure switch is one detecting the presence of fluid pressure.…
Filled-bulb systems exploit the principle of fluid expansion to…
A sliding-stem valve body is one where the moving parts slide with a…
A fundamental limitation of proportional control has to do with its…
The simple PLC ladder diagram (LD) commands consist of contacts and…
A 4 to 20 mA current signal represents some signal along a 0 to 100…
Suppose we wished to measure the rate of propane gas flow through a…
Learning is not merely a process of information transfer. It is first…
A quantitative PID tuning procedure is a step-by-step approach leading…
Classical mechanics (often called Newtonian mechanics in honor of…
The advent of “smart” field instruments containing…
The disadvantages of pneumatic instruments are painfully evident to…
A limitation inherent to pneumatic valve actuators is the amount of…
First, let us review some of the properties of differentials and…
Regardless of valve type, all stem-actuated control valves require…
Impedance in a series circuit is the orthogonal sum of resistance and…
Those familiar with industrial instrumentation will find much within…
In some process applications, it is important that the control valve…
The vast majority of modern process transmitters (both analog and…
Thermodynamics is the study of heat, temperature, and their related…
The next level of detail is the Process and Instrument Diagram, or…
Level gauges are perhaps the simplest indicating instrument for liquid…
“Radio” systems use electromagnetic fields to communicate…
The Law of Continuity for fluids states that the product of mass…
A limitation inherent to pneumatic valve actuators is the amount of…
To show a practical process example, let’s examine three…
Perhaps the most valuable skill an instrument technician can possess…
Hydrogen ion activity in aqueous (water-solvent) solutions is a very…
In order to provide an interface between the internal (digital) world…
For better or worse, there are no fewer than three different forms of…
Self-balancing pneumatic instrument mechanisms are very similar to…
Sensors used to measure vibration come in three basic types:…
A quantitative PID tuning procedure is a step-by-step approach leading…
The disadvantages of pneumatic instruments are painfully evident to…
A different strategy for controlling the flow of fluid is to insert a…
Up until this point, we have explored various types of instrumentation…