4th Class Power Engineering Unit A9: Energy Plant Instrumentation and Controls Questions with Verified Solutions

4th Class Power Engineering Unit A9: Energy Plant Instrumentation and Controls Questions with Verified Solutions A _________ controls the flow of air through ducts or wall openings: Select one: a. damper b. control valve c. fan d. pilot a In a simple control system a process variable is measured and: Select one: a. compared with a set point value b. compared with normal operating trends c. charted in a graph d. charted in the CPU a This type of PLC cannot be expanded: Select one: a. field transmitter b. modular c. monolithic d. programmable c Glass stem thermometers are also known as: Select one: a. thermowells b. thermocouples c. liquid in glass thermometers d. filled system thermometers c The difference between the actual value of the measured variable and the set point is a: Select one: a. disturbance b. composition c. deviation d. divination c This type of thermostat is equipped with an open-contact switch or a snap switch: Select one: a. on-off control b. two position c. modulating d. multipositon a It is common for _________ to be attached to a pen mechanism of a chart recorder: Select one: a. helical and spiral capillary tubes b. helical and spiral bourdon tubes c. helical and spiral dampeners d. helical and spiral pig tails b A two-terminal variable resistor used for varying current in a circuit is known as a: Select one: