The control range of a proportional temperature controller i

The control range of a proportional temperature controller is from 500 degree F to 1500 degree F. The proportional band is 20%. The control is set at 1100 degree F with the control valve 60% open. What temperature will cause the control valve to go fully closed?

Solution

Temparatire when control valve to go fully closed is given by

T = (1500-500)*0 + 500 = 500⁰ F