Application - Siemens SIPROTEC 4 7XT34 Produktinformation

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Application

The 20-Hz Band-pass Filter 7XT34 is used in combination with the 20-Hz generator
7XT33 for the 7UM62 machine protection and 7UM85 generator protection.
In this connection, the 20-Hz generator is the source for biasing the generator neu-
tral point in order to implement a 100 % stator ground fault protection.
Biasing can be accomplished, for example, by connecting the 7XT33 and 7XT34 to
the load resistor of a grounding transformer or neutral point transformer.
The 100 % stator ground fault protection detects ground faults in the stator winding
of generators which are connected to the power system over a generator trans-
former.
The protection device that works with the 7XT33 and 7XT34 detects ground faults
in the entire winding area, including the machine neutral point.
The applied measuring principle works independently of the generator operating
principle and also allows measurements to be performed with the generator at
standstill.
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SIPROTEC 4, 20-Hz Band-pass Filter 7XT34, Product Information
C53000-B1174-C130-5, Edition 09.2016