Sequence of Events Reports and Fault Recording
GARD 8000 Distance Relay
RFL Electronics Inc.
10.2.3
DIGITAL FAULT RECORDING
The GARD 8000 provides powerful digital fault recording as part of the distance relay module. The
oscillography is captured with 32 samples per cycles, up to a total of 15 seconds.
The oscillographic records are stored in non-volatile memory. In case of loss-of-power, the records are
guaranteed to remain in memory for a minimum of 27 days.
Fault records are captured and stored in COMTRADE binary format, according to IEEE C37.111-
1999. Any COMTRADE reader can be used for fault analysis, including the versatile Analyzer
provided as part of the ZIVerCom Application program.
10.2.4
ANALOG AND DIGITAL CHANNELS
The GARD 8000 distance relay module has nine analog channels: 5 currents and 4 voltages. They are:
3 PHASE CURRENTS
3 phase voltages
1 neutral current used for sensitive ground fault relaying or current polarization or the directional units
1 neutral current from a parallel line used for mutual coupling compensation of the fault locator
1 voltage input for a bus voltage used in the synch check unit
The digital channels to be recorder are defined in the ‘Oscillography Mask’ settings.
10.2.5
TRIG CONDITIONS
A digital fault record will be triggered by pick-up of any of the elements selected in the oscillography
mask.
10.2.6
PRE-FAULT TIME
The pre-fault time can be set between 0 and 25 cycles.
10.2.7
LENGTH OF OSCILLOGRAPHIC RECORD
A maximum of 725 cycles can be recorded in the memory. The number of fault records depends on the
length selected for the recording. Maximum number of records is 64 and they are related to the set
length as shown in the Table below.
Table 10-1. Oscillographic Record
Set number of cycles
Maximum number of records
725 1
350 2
175 3
... ...
22 32
11 64
March 1, 2009
10-12
973.334.3100
