Admittance

In electrical engineering, the admittance (Y) is the inverse or reciprocal of the impedance (Z). The SI unit of Admittance is the siemens.

$Y = Z^{-1} = 1/Z \,$

where

Y is the admittance, measured in siemens

Z is the impedance, measured in ohms

Just as impedance is complex resistance, and the conductance G is the inverse G = 1/R of resistance R, admittance is also complex conductance.

Likewise, admittance is made up of a real part (the conductance), and an imaginary part (the susceptance B), shown by the equation

$Y = G + j B \,$

The magnitude of admittance is given by:

$\left | Y \right | = \sqrt {G^2 + B^2} \,\!$

where

G is the conductance, measured in siemens

B is the susceptance, measured in siemens

SI electricity units