Siemens SIPROTEC 7VU681, Руководство пользователя

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Mounting And Commissioning
3.3 Commissioning
SIPROTEC, 7VU681, User Manual
C53000-G1176-C368-1, Release Date 07.2012
92
Amplitudes
Read out voltages in all three phases in the operational measured values and compare with the actual voltages.
The voltage of the positive sequence system U1 must be approximately the same as the indicated phase volt-
ages. If there are significant deviations, the voltage transformer connections are incorrect.
Phase Rotation
The phase rotation must conform with the configured phase sequence ; otherwise an indication "Fail Ph.
Seq.V.B1" or "Fail Ph. Seq.V.B2" will be output. The allocation of measured values to phases must be checked
and corrected, if necessary. If significant deviations are found, check, and if necessary correct, the voltage
transformer circuits and repeat the test. It is also possible to use for this check the operational measured value
of positive-sequence component U1 of the voltages: With U1
≠
U
L
-E a wiring error is indicated.
3.3.7 Checking the Current Circuits
General
The checks of the current circuits are performed with the generator to ensure correct CT circuit connections
with regard to cabling, polarity, phase sequence, CT ratio etc., not in order to verify individual protection
functions in the device.
Test Instruction
Then the checks of the current transformer circuits are carried out with max. 20 % of the rated transformer
current. Tests with generator currents of more than 20 % are not normally required for digital protection.
Amplitude Values
The currents can be read out from the device front panel or from the PC via the operator interface under
operational measured values and compared with the actual measured values. If significant deviations are
found, the CT connections are not correct.
3.3.8 Creating a Test Fault Record
General
At the end of commissioning, an investigation of switching operations of the circuit breaker(s) or primary
switching device(s), under load conditions, should be done to assure the stability of the protection during the
dynamic processes. A maximum of information on protection behaviour is supplied by fault recordings.
Requirement
Along with the capability of storing fault recordings via pickup of the protection function, the 7VU681 also has
the capability of capturing the same data when commands are given to the device via the service program
DIGSI, the serial interface, or a binary input. For the latter, event ">Trig.Wave.Cap." must be allocated to a
binary input. Triggering of the recording then occurs, for example, via the binary input when the protection
object is energised.
Such externally started test fault recordings (that is, without a protection pickup) are handled by the device as
normal fault recordings, i.e. for each measurement record a fault log is opened with its own number, for
unequivocal allocation. However, these recordings are not displayed in the fault indication buffer, as they are
not fault events.