Siemens SENTRON 3WL10 - Characteristic Curves

The operating value is described as factor >1 of the line frequency - settable to 50Hz or
60Hz.
In this way, the distribution board can be protected from impermissible deviations in the line
frequency.
Undervoltage protection (V
u
)
The undervoltage protection responds with a de󹪝nable de󹪝nite-time delayt
u
(U) as soon as a
phase-to-phase voltage (U
ph
-U
ph
) falls below the operating valueU
u
.
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.
Overvoltage protection (V
o
)
The overvoltage protection responds with a de󹪝nable de󹪝nite-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.
2.9.4.1 Characteristic curves
The settings selected for the trip unit of a circuit breaker depend on the technical environment
(e.g. switchboard and applications) and the type of equipment to be protected. It is the
responsibility of the system planner to calculate and dimension the protection settings in
accordance with the valid rules.
The following diagram shows the tripping characteristics of the circuit breaker.
Description
2.9Electronic trip unit ETU
3VA27 molded case circuit breakers & 3WL10 air circuit breakers
60 Equipment Manual, 10/2023, L1V30499596002-03