Application Guide - NP900 Series
168 (504
)
A996A
voltage level. Protection stages can be set to protect against under- or overvoltage.
Blocking signal and setting group selection controls the operating characteristics of the
function during normal operation.
3.2.16.1
P
OSITIVE SEQUENCE VOLTAGE CALCULATION
Below is presented the formula for symmetric component calculation and therefore to VUB
positive sequence calculation.
U1 = 1 3
�
(U
L1
+ aU
L2
+ a
2
U
L3
)
a = 1
∠
120°
a
2
= 1
∠
240°
U
L1
…
3
= Line to neutral voltages