Functions
2.1 General
SIPROTEC, 7SJ62/64, Manual
C53000-G1140-C207-2, Release date 01.2008
52
2.1.4
Oscillographic Fault Records
The Multi-Functional Protection with Control 7SJ62/64 is equipped with a fault record memory. The instanta-
neous values of the measured quantities
i
A
, i
B
, i
C
, i
N
or i
NS
and v
A
, v
B
, v
C
, v
N
or 3 · v
0
and v
SYN
(only 7SJ623/624 and 7SJ64)
(voltages in accordance with connection) are sampled at intervals of 1.25 ms (at 50Hz) and stored in a revolving
buffer (16 samples per cycle). In the case of a fault, the data is recorded for a set period of time, but not for
more than 5 seconds. The total duration of recording amounts to up to 20 seconds. Up to 8 fault records can
be recorded in this buffer. The fault record memory is automatically updated with every new fault, so that there
is no acknowledgment for previously recorded faults required. In addition to protection pickup, the fault record
buffer can also be started via a binary input or the serial interface.
2.1.4.1
Description
The data can be retrieved via the serial interfaces by means of a personal computer and evaluated with the
protection data processing program DIGSI and the graphic analysis software SIGRA 4. The latter graphically
represents the data recorded during the system fault and also calculates additional information from the mea-
sured values. Currents and voltages can be presented as desired as primary or secondary values. Signals are
additionally recorded as binary tracks (marks), e.g. "pickup", "trip".
If the device has a serial system interface, the fault recording data can be passed on to a central device via this
interface. The evaluation of data is done by appropriate programs in the central device. Currents and voltages
are referred to their maximum values, scaled to their rated values and prepared for graphic representation.
Signals are additionally recorded as binary tracks (marks), e.g. "pickup", "trip".
Transfer to a central device can be polled automatically, either after each fault detection by the protection, or
only after a trip.
Note
The signals used for binary tracks can be configured in DIGSI.
Note
If via parameter
251
CT Connect.
one of the current transformer connection types
A,G2,C,G; G->B
or
A,G2,C,G; G2->B
has been selected, the measured ground current
I
N2
measured by the second current
transformer is indicated under track „iN“. The ground current detected by the fourth current transformer is indi-
cated under track „iNs“ angezeigt.
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