Siemens SIPROTEC 7UT613 series, Руководство пользователя

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2 Functions
260
7UT613/63x Manual
C53000-G1176-C160-2
Figure 2-105 Logic diagram of the overvoltage protection
2.15.2 Setting Notes
General The application of overvoltage protection is only possible in 3-phase protected objects.
Furthermore, it is a prerequisite that the device is connected to a three-phase voltage
transformer set.
Overvoltage protection is only effective and accessible if address
153
was set to
OVERVOLTAGE Enabled
during configuration of the protection function (section
2.1.3).
Under address
5301 OVERVOLTAGE
the overvoltage protection
ON
or
OFF
can be set.
Furthermore, the command can be blocked if the protective function is enabled
(
Block relay
).
Pickup Values,
Times Address
5318
A
VALUES
serves to specify the measured quantities used by the pro-
tection feature. Setting
U-ph-ph
evaluates the phase-phase voltages. This is not in-
fluenced by displacement voltages that occur during ground connections or earth
faults at a certain distance from the grounding point. The setting
U-ph-e
of the phase-
earth voltage reflects the actual insulation damage against earth and can also be used
in an earthed starpoint. This parameter can only be set with DIGSI at
Additional Set-
tings . Please note that the setting values for the voltages always refer to the phase-
phase voltages, even though the measured values phase-earth have been selected.
The settings of the voltage threshold and the timer values depend on the type of ap-
plication. Stage U> records stationary overvoltages. It is set to approx. 5 % above the
maximum stationary operating voltage that is expected in operation. If the overvoltage
protection is assigned to one side of the main protected object or the three-phase