Siemens SIPROTEC 7UT613 series, Manual, Page: 18 / 638

1 Introduction
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7UT613/63x Manual
C53000-G1176-C160-2
1.1 Overall Operation
The digital differential protection devices SIPROTEC 4 7UT613/63x are equipped with
a powerful microprocessor system. This provides fully numerical processing of all
functions in the device, from the acquisition of the measured values up to the output
of commands to the circuit breakers
Figure 1-1 Hardware structure of the digital differential current protection relay 7UT613/63x
— Example of a 7UT613 for a three-winding transformer with measuring loca-
tions M1, M2 and M3, with 3 auxiliary 1-phase inputs X1, X2 and X3
Analogue Inputs The analogue inputs (AI) transform the currents and voltages derived from the instru-
ment transformers and match them to the internal signal levels for processing in the
device. Depending on the version, the device features between 12 current inputs
(7UT613/7UT633) and 16 current inputs (7UT635). Three current inputs are provided
for the input of the phase currents at each end of the protected zone (= measuring
points), further measuring inputs (= additional inputs) may be used for any desired cur-
rent, e.g. the earth current measured between the starpoint of a transformer winding