A three-element feedwater regulator is controlled by which of the following?

A three-element feedwater regulator is primarily designed to maintain the correct water level in the steam drum of a boiler, ensuring proper operation and efficiency. The regulator achieves this by dynamically measuring and reacting to three key parameters: steam flow, feedwater flow, and drum level.

Steam flow measurement is crucial because it tells the system how much steam is being consumed by the connected processes. Understanding this allows the feedwater regulator to adjust and provide the necessary amount of feedwater to maintain the proper level in the drum.

Feedwater flow is monitored to ensure that the amount of water being added to the boiler can match the steam production rate effectively. This is essential to prevent fluctuations in drum water level, which can lead to operational issues.

Drum level is critical because it indicates the actual water level within the drum. Maintaining this level is essential to prevent low water conditions that could lead to boiler damage or high water conditions that could cause carryover of water into the steam lines.

By using these three parameters, the regulator can make real-time adjustments to keep the water level stable, ensuring safe and efficient boiler operation.