GE L90 Instruction Manual page 286

PRODUCT SETUP
• Events — Nine before trigger and seven after trigger (only available via the relay web page)
• Fault duration times for each breaker (created by the breaker arcing current feature)
The captured data also includes the fault type, the distance to the fault location, distance to the fault location, fault loop
impedance, as well as the reclose shot number (when applicable). To include fault duration times in the fault report, enable
and configure the breaker arcing current feature for each of the breakers. Fault duration is reported on a per-phase basis.
The relay allows locating faults, including ground faults, from delta-connected VTs. In this case, the missing zero-sequence
voltage is substituted either by the externally provided neutral voltage (broken delta VT) connected to the auxiliary voltage
channel of a VT bank, or by the zero-sequence voltage approximated as a voltage drop developed by the zero-sequence
current, and user-provided zero-sequence equivalent impedance of the system behind the relay.
The trigger can be any FlexLogic operand, but in most applications it is expected to be the same operand, usually a virtual
output, that is used to drive an output relay to trip a breaker. To prevent the overwriting of fault events, do not use the
disturbance detector to trigger a fault report. A FAULT RPT TRIG event is automatically created when the report is triggered.
If a number of protection elements are ORed to create a fault report trigger, the first operation of any element causing the
OR gate output to become high triggers a fault report. However, If other elements operate during the fault and the first
operated element has not been reset (the OR gate output is still high), the fault report is not triggered again. Considering
the reset time of protection elements, there is very little chance that a fault report can be triggered twice in this manner. As
the fault report must capture a usable amount of pre and post-fault data, it cannot be triggered faster than every 20 ms.
Each fault report is stored as a file; the relay capacity is 15 files. A 16th trigger overwrites the oldest file.
Individual fault report features store their files in the same memory space. The sixteenth report overwrites the first one
regardless of which fault report feature produced the sixteenth and the first records.
The EnerVista software is required to view all captured data. The relay faceplate display can be used to view the date and
time of trigger, the fault type, the distance location of the fault, and the reclose shot number.
5
The
FAULT REPORT 1 SOURCE
breaker applications where the line current is supplied individually from two breaker CTs, the fault locator source should
include the sum of currents from both CTs as well as the line voltage. For the application of entirely parallel lines, the fault
report can be programmed to apply compensation for the zero sequence mutual coupling between parallel lines when
calculating fault resistance and fault loop impedance. If this compensation is required, the ground current (3I_0) from the
parallel line must be connected to the ground input CT of the CT bank configured under the
the same polarity as the phase current input configured in the same source.
The
FAULT 1 REPORT TRIG
operational fault location calculations. The distance to fault calculations are initiated by this signal. The
,
MAG FAULT REPORT 1 Z0 MAG
For a two-terminal line application, the
and
REPORT 1 Z0 ANG
For the application of entirely parallel lines, Z0M MAG/ANG is the mutual zero-sequence impedance for the whole line,
required to compensate the calculation of fault resistance and fault loop impedance. For a three-terminal application,
these settings are used to enter the line segment impedance and length from the local terminal to the tap point only. The
figure shows the supported configurations of parallel lines in three-terminal applications.
5-100
setting selects the source for input currents and voltages and disturbance detection. For dual-
setting assigns the FlexLogic operand representing the protection element/elements requiring
, and
FAULT REPORT 1 Z0M MAG
FAULT REPORT 1 Z1 MAG
settings for the entire line must to be entered for fault location calculations.
FAULT REPORT 1 LENGTH
impedances are entered in secondary ohms.
, ,
FAULT REPORT 1 Z1 ANG FAULT REPORT 1 Z0 MAG
L90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS
with
FAULT REPORT 1 SOURCE
FAULT REPORT 1 Z1
,
FAULT