Susceptance

In electrical engineering, the susceptance (B) is the imaginary part of the admittance. In SI units, the susceptance is measured in siemens

$Y = G + j B \,$

where

Y is the admittance, measured in siemens

G is the conductance, measured in siemens

$j = \sqrt{-1} \,$

B is the susceptance, measured in siemens.

The admittance (Y) is the inverse of the impedance (Z)

$Y = 1/Z \,$

where

$Z = R + j X \,$

Z is the impedance, measured in ohms

R is resistance, measured in ohms

X is the reactance, measured in ohms.

Note: The susceptance is NOT the inverse of the reactance.

The magnitude of admittance is given by:

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

SI electricity units