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5
Protection related functions
5.1
Three-phase inrush detector INRPHAR (ANSI 68HB)
5.1.1
Identification
Function description
IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Three-phase inrush detector
INRPHAR
3I2f>
68HB
5.1.2
Function block
Figure 656: Function block
5.1.3
Functionality
The three-phase inrush detector function INRPHAR is used to detect transformer
inrush situations in distribution networks.
Transformer inrush detection is based on the following principle: the output signal
BLK2H
is activated once the numerically derived ratio of second harmonic current
I_2H and the fundamental frequency current I_1H exceeds the set value.
The operate time characteristic for the function is of definite time (DT) type.
The function contains a blocking functionality. Blocking deactivates all outputs and
resets timers.
5.1.4
Analog channel configuration
INRPHAR has one analog group input which must be properly configured.
Table 1103: Analog signals
Input
Description
I3P
Three-phase currents
1MRS759142 F
Protection related functions
REX640
Technical Manual
1157