130 A). This curve also applies cable networks with to
20 nominal voltage with small component overhead cables even their
neutral point isolated.Page 27
Applications
If detuning specified percentage, the expected reactive current across the faulty
section calculated according the following formula
( )
100
res fix
v
I v
I
(1. Ires equal the
grid's capacitive current, when earth fault occurs
Ifix Current connected fixed coil grid
v Detuning %
In very large grids, the values recommended VDE 0228 Part for the self-extinguishing
current limit may exceeded (up kV: 110 ca.24)
Iv Detuning current (reactive current A
Ires Current through the adjustable P-coil the resonance point.
Figure 11: Self-extinguishing current limit accordance with VDE 0228, Part 2
Curve Self-extinguishing current limit for earth-fault residual current for grids with
earth-fault compensation.
Curve Networks with isolated neutral point.
nominal voltage
earth
fault
curren
t
