Siemens 7SJ85 - Structure of the Function; Function Description

The current measurement is based on the RMS values of the fundamental component.
Structure of the Function
The Current-balance supervision function is located in the Power-system data of each 3-phase current
measuring point.
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Figure 9-24 Structure/Embedding of the Function
Function Description
The current balance is checked by a magnitude monitoring function. This function relates the smallest phase
current to the largest phase current. Unbalance is detected if
|Imin| / |Imax| < Threshold min/max, as long as Imax > Release threshold.
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Figure 9-25 Characteristic of the Current-Balance Supervision
9.3.10.2
9.3.10.3
Supervision Functions
9.3 Supervision of the Secondary System
SIPROTEC 5, Overcurrent Protection, Manual 1273
C53000-G5040-C017-8, Edition 07.2017