5
Protection related functions
5.1
Three-phase inrush detector INRPHAR
5.1.1
Identification
Function description
IEC 61850
identification
IEC 60617
identification
ANSI/IEEE
C37.2 device
number
Three-phase inrush detector
INRPHAR
3I2f>
68
5.1.2
Function block
Figure 418: Function block
5.1.3
Functionality
The three-phase inrush detector function INRPHAR is used to coordinate
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
Operation principle
The function can be enabled and disabled with the
Operation setting. The
corresponding parameter values are "On" and "Off".
The operation of INRPHAR can be described using a module diagram. All the
modules in the diagram are explained in the next sections.
1MRS757644 H
Protection related functions
620 series
Technical Manual
801