Note 1 to entry: The transfer function of an ideal proportional plus integral plus derivative element is given by

${\displaystyle \frac{V\left(s\right)}{U\left(s\right)}=K_{\text{Ρ}}\cdot \left(1+\frac{1}{T_{\text{i}}\cdot s}+T_{\text{d}}\cdot s\right)}$

where

KP	is the proportional action coefficient;
Td	is the rate time;
Ti	is the reset time;
s	is the complex variable of the Laplace transform;
U(s)	is the input transform;
V(s)	is the output transform.

Note 2 to entry: This entry was numbered 351-28-30 in IEC 60050-351:2006.