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Description
2.8 Electronic trip unit ETU
3VA27 molded case circuit breakers & 3WL10 air circuit breakers
Manual, 10/2018, L1V30499596002-01
65
Overvoltage protection (V
o
)
The overvoltage protection responds with a definable definite-time delay t
o
(U) as soon as a
phase-to-phase voltage (U
ph
-U
ph
) rises above the operating value U
o
.
The operating value is described as factor > 1 of the rated voltage U
n
of the power system.
The rated voltage U
n
can be variably set from 100 V to 690 V.
In this way, the distribution board can be protected from impermissible deviations in the line
voltage.