Inversion of Phase Sequence (Phase Sequence Reversal)
279
7UM62 Manual
C53000-G1176-C149-3
2.43
Inversion of Phase Sequence (Phase Sequence Reversal)
2.43.1 Functional Description
General
A phase rotation feature via binary input and parameter is implemented in the 7UM62,
thus ensuring that all protective and monitoring functions operate correctly when the
phase rotation is reversed.
If an anti-clockwise rotating phase sequence permanently exists, the appropriate
setting should be entered in the power system data (see Section 2.3).
If the phase rotation reverses during operation (e.g. in a pumping power station, the
transition from the generator operation to the pumping operation is realized by
changing the phase rotation), then a reversal signal at the input masked for this
purpose is sufficient to inform the protective relay of the phase-sequence reversal.
Logic
The phase rotation is permanently set in a parameter of the power system data at
address
0271
. The binary input ”
” sets the phase
rotation for the opposite of the setting (see figure 2-130).
Figure 2-130 Message Logic of the Phase-Sequence Reversal
For safety reasons, the device accepts the phase rotation reversal only by a time when
no usable measured quantities exist. The binary input is only inquired if operational
condition 1 is not present. If a reverse command is present for a period of at least
200 ms, the measured quantities of phases L2 and L3 exchanged.
If operational condition 1 is reached before the minimum control time of 200 ms has
expired, the phase rotation reversal does not become effective.
As no phase rotation reversal is possible in operational condition 1, the control signal
could be cancelled in operational condition 1 without a phase rotation. For safety
reasons, the control signal should be permanently present in order to avoid
malfunctions also in case of a device reset (e.g. due to configuration change).
L1 L3 L2
L1 L2 L3
”1”
OR
>
>
OR
200 ms
&
&
&
&
OR
&
FNo. 05145
FNo. 05002
FNo. 05148
FNo. 05147
