Siemens SIPROTEC 4 7SJ61 User Manual

Oscillographic Fault Records
The Multi-funktional Protective Relay with Bay Controller 7SJ61 is equipped with a fault record memory. The
instantaneous values of the measured quantities
i
A
, i
B
, i
C
, i
N
or i
Ns
are sampled at intervals of 1.25 ms (for 50 Hz) and stored in a ring buffer (16 samples per cycle). In the event
of a fault, the data are recorded for a set period of time, but not longer than 5 seconds. The total duration of
recording amounts to up to 20 seconds. A minimum of 8 fault records can be recorded in this buffer. The fault
record memory is automatically updated with every new fault, so no acknowledgment for previously recorded
faults is required. In addition to the protection pickup, the fault record buffer can also be triggered via binary
input, the integrated user interface and the serial interface.
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
measured values. Currents 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 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.
i
i
NOTE
The signals used for binary tracks can be configured in DIGSI.
i
i
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 Ι
N2
measured by the second current
transformer is indicated under track “iN”. The ground current detected by the fourth current transformer is
indicated under track “iNs”.
Setting Notes
Configuration
Fault recording (waveform capture) will only take place if address 104 OSC. FAULT REC. is set to Enabled.
Other settings pertaining to fault recording (waveform capture) are found in the Osc. Fault Rec.
submenu of the SETTINGS menu. Waveform capture makes a distinction between the trigger instant for an
oscillographic record and the criterion to save the record (address 401 WAVEFORMTRIGGER). Normally, the
trigger is the pickup of a protection element, i.e. the time 0 is defined as the instant the first protection func-
tion picks up. The criterion for saving may be both the device pickup (Save w. Pickup) or the device trip
(Save w. TRIP). A trip command issued by the device can also be used as trigger instant (Start w.
TRIP), in this case it is also the saving criterion.
A fault event starts with the pickup by any protection function and ends when the last pickup of a protection
function has dropped out. Usually this is also the extent of a fault recording (address 402 WAVEFORM DATA =
Fault event). If automatic reclosing is performed, the entire system fault — with several reclosing attempts
if necessary — can be recorded until the fault has been cleared for good (address 402 WAVEFORM DATA =
Pow.Sys.Flt.). This facilitates the representation of the entire system fault history, but also consumes
storage capacity during the automatic reclosing dead time(s).
2.1.4
2.1.4.1
2.1.4.2
Functions
2.1 General
SIPROTEC 4, 7SJ61, Manual 41
C53000-G1140-C210-6, Edition 05.2016

Siemens SIPROTEC 4 7SJ61 Specifications

General

Brand	Siemens
Model	SIPROTEC 4 7SJ61
Category	Relays
Language	English