Question

A PID controller has the transfer fucntion $2+\frac{0.4}{s}$ with the unit of time expressed in minutes. The parameters proportional band and reset time for the above controller are respectively.

• A. 200% and 0.4 min
• B. 50% and 0.4 min
• C. 200% and 5 min
• D. 50% and 5 min

Answer 1

The correct option is D 50% and 5 min

$T\left(s\right)=2+\frac{0.4}{s}=2(1+\frac{0.2}{s})$
Gain = 2

Proportional band
$=\frac{100}{Gain}=\frac{100}{2}=50\%$
$Resettime=\frac{1}{0.2}=5min.$