Boiler Drum Level Control ( 3 Element Control)

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Three-element Drum-level Control

Three-element drum-level control is suited for handling variable feed water pressure or multiple boilers with multiple feed water pumps. In this design, three elements are used, each for controlling level, steam and feed water flow respectively. This system offers far better and advanced drum level control as compared to all other systems. For best control, correct flow values of both steam as well as feed water must be maintained with regard to density. A typical drum level control with three element module is shown in the figure below.
THREE DRUM.jpg

Notes:

https://drive.google.com/file/d/0B-ZhnHb2X39pTV9jOHg1ZnVvVW8/view?usp=sharing

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