Figure. 5.3.3. - 50. Angle tracking of Idir> function (3LN/3LL + U
0
mode).
Please note in the picture above that the tripping area is linked to the angle of the positive sequence
voltage
U
1
. The angle of the positive sequence current
I
1
is compared to
U
1
angle, and if the fault is in
the correct direction, it is possible to perform a trip when the amplitude of
I
L1
,
I
L2
or
I
L3
increases
above the pick-up limit.
If the 3LL mode is used without the
U
0
measurement in a single-phase fault situation, the voltage
reference comes from the healthy phase and the current reference from the faulty phase. In a short-
circuit the angle comes from impedance calculation.
Events and registers
The directional overcurrent function (abbreviated "EMON" in event block names) generates events and
registers from the status changes in ALARM events. The user can select the status ON or OFF for
messages in the main event buffer.
The triggering event of the function is recorded with a time stamp and with process data values.
Table. 5.3.3. - 54. Event codes.
Event number
Event channel
Event block name
Event code
Description
8644
135
EMON1
4
Idir> (67) Detect ON
8645
135
EMON1
5
Idir> (67) Detect OFF
The function registers its operation into the last twelve (12) time-stamped registers. The table below
presents the structure of the function's register content.
Table. 5.3.3. - 55. Register content.
Date and time
Event
code
Fault
type
Max I
m
/I
set
Operating
angle
Used SG
dd.mm.yyyy
hh:mm:ss.mss
8644-8645
Descr.
L1-G…
L1-L2-L3
The ratio between the highest phase current
and the pick-up value.
0...250°
Setting
group 1...8
active.
AQ-E215
Instruction manual
Version: 2.01
© Arcteq Relays Ltd
72