UFC 3 -430-11
14 February 2001
three element control system corrects the problems associated with a two element
control system and provides the best method of compensating for variable loads.
7-5
routing the steam from each individual boiler into a commo n plant output header. The
pressure measured at this plant output header will be feed back into each individual
boiler control loop. Control is maintained by the plant master cascading the output of
the boiler masters to achieve the desired steam output. A typical multiple boiler control
loop is shown in Figure 7 -10. Dual Pressure Indicating Transmitters (PIT) and Pressure
Indicating Controllers (PIC) are shown feeding their output signals into a High Select
continued plant operations during maintenance or failure of one PIT or PIC.
7-3
Previous Page
