A newly-installed pH transmitter does not seem to be measuring the pH of the process liquid accurately. The indicating controller’s…
Suppose you wish to calibrate a current-to-pressure (“I/P”) transducer to an output range of 3 to 15 PSI, with an…
Suppose the electric motor refuses to run when the “Run” pushbutton switch is pressed. A technician begins diagnosing electric motor…
Examine these two pneumatic control loops (transmitter-controller-valve systems) for an industrial boiler, controlling both water level and steam pressure: Pneumatic…
You have to Identify Instrumentation Terms in Water Supply System in this example problem. A water reservoir located high on…
Explain what the following PLC Practice Questions on “ladder-logic” circuit does, and identify the meaning of each symbol in the diagram: PLC…
A very useful technique for testing process control loop response is to subject it to a “step-change” in controller output.…
A level control loop is supposed to maintain a constant level of liquid at the bottom of the stripping tower where…
A engineer needs to write a PLC program to control a water pump driven by an electric motor. This water…
An operator reports a high level alarm (LAH-12) displayed at the control room for the last 13 hours of operation,…
