Question 144Steam Plants - Assistant Engineer

The correct answer is C) feed water flow measurement. The two-element feed water regulator functions similarly to the three-element feed water regulator, but it does not utilize feed water flow measurement. Instead, it relies on the measurement of water level and steam flow to control the feed water supply, whereas the three-element regulator also incorporates feed water flow measurement. The other options are incorrect because the two-element regulator does use water level (A) and drum pressure (D) measurements, but it does not use feed water flow measurement (C), which is the key difference from the three-element regulator.