Siemens Siprotec 7UM611, Руководство пользователя

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2 Functions
36
7UM61 Manual
C53000-G1176-C127-3
Uph/Uen Adaption
Factor The address
225
serves to communicate the adaptation factor between the phase
voltage and the displacement voltage to the device. This information is relevant for
measured quantity monitoring.
If the voltage transformer set has e-n windings connected to the device (UE input), this
must be specified accordingly in address
223
(see above margin heading "UE Input").
Since transformation between voltage transformers usually is as follows:
with connected Uen voltage the Uph/Uen factor (secondary voltage, address
225 Uph
/ Udelta
) must be set to 3/
√
3 =
√
3 = 1.73. For other transformation ratios, i.e. the
formation of the displacement voltage via an interconnected transformer set, the factor
must be corrected accordingly.
Rated System Fre-
quency The nominal frequency of the system is set in Address
270 Rated Frequency
. The
factory setting of the model variant must only be changed if the device is to be used
for a purpose other than intended when ordering.
Phase Rotation Address
271 PHASE SEQ.
is used to change the default phase sequence (
L1 L2 L3
for clockwise rotation), if your power system permanently has an anti-clockwise phase
sequence (
L1 L3 L2
). A temporary reversal of rotation is also possible using binary
inputs (see Section 2.33).
Figure 2-3 Phase sequences
Operating Mode The
272 SCHEME
setting is used for specifying if the generator to be protected is op-
erated in
Unit transf.
or in
Busbar
mode. This specification is important for stator
earth fault connection and for the inverse O/C time protection with undervoltage con-
sideration, as different voltages are used here, depending on the corresponding oper-
ating mode (see "Undervoltage Consideration" in Section 2.8).
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