Parameter Value
Description
Disabled
This element is switched out and is not available
Enabled
The element is available for use and can be parame-
terized
Parameter:
81HB2 Setting
•
Default setting:
0.2.I
This setting defines the operating threshold of the element. The ratio of the second harmonic component
of current compared to the fundamental component of current is exceeded.
This setting should be set to the default value unless in-service experience produces incorrect operation.
Parameter:
81HB2 Bias
•
Default setting:
Cross
Selects whether fundamental frequency RMS or the true RMS value of the measured currents used.
Parameter Value
Description
Cross
The ratio of second harmonic component to funda-
mental frequency component for each phase is moni-
tored independently.
A
2nd
: A
Fund
B
2nd
: B
Fund
C
2nd
: C
Fund
All phases are inhibited when the ratio of second
harmonic component to fundamental frequency
component in any phase exceeds setting.
Phase
The ratio of second harmonic component to funda-
mental frequency component for each phase is moni-
tored independently.
A
2nd
: A
Fund
B
2nd
: B
Fund
C
2nd
: C
Fund
Individual phase outputs are given when the ratio
exceeds setting on the relevant phase.
Sum
The ratio of the ‘square root of the sum of the squares
of all second harmonics’ is compared to each funda-
mental frequency component individually.
Individual phase outputs are given when the ratio
exceeds setting on the relevant phase.
Supervision Functions
6.6 81HB2 Inrush Current Detection
366
Reyrolle 7SR5, Transformer Protection Device, Device Manual
C53000-G7040-C015-1, Edition 11.2019