81HB2 Inrush Current Detection
Overview of Functions
The elements can be used to block operation of selected functions where these are liable to mal-operate
during transformer switch in conditions.
Structure of the Function
The inrush detector function has group dependent settings. These settings can be different in each set-tings
group – group numbers (Gn) 1 to 4.
This function corresponds to the logical nodes
A81HB2PHAR*
in IEC 61850.
The function monitors the primary system using the 3 phase current inputs e.g. CT1/2/3.
The inrush detector function (81HB2) is summarized below:
•
High speed (instantaneous) operate characteristic
•
Logic outputs are provided to block selected device functionality and for external indications
Logic of the Function
[lo_7SR5_81HB2logicdiagram, 1, en_US]
Figure 6-15
Logic Diagram: 81HB2 Inrush Current Detection
Application and Setting Notes
Parameter:
81HB2 Element
•
Default setting:
Disabled
This setting is used to allow the element to be switched on and off if it is not required. A separate setting
is provided for each element. These setting can be used to select the number of elements required.
6.6
6.6.1
6.6.2
6.6.3
6.6.4
Supervision Functions
6.6 81HB2 Inrush Current Detection
Reyrolle 7SR5, Transformer Protection Device, Device Manual
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C53000-G7040-C015-1, Edition 11.2019