The relay generates a detailed event report after every fault. This report includes all data
needed to quantitatively examine the prefault, fault, and postfault voltages and currents.
Parameters such as fault current sensed by the relay, relay response time, and total fault
clearing time can easily be determined. The event report includes the distance to the fault,
fault type, and the state of all relay units during the event. Each event is time-tagged by a
self-contained clock. In addition to the automatic generation of this report for faults, you may
generate a report upon command, or by asserting one of several control inputs to the
instrument. This allows users to trigger the report from other equipment, such as
oscillographic starting units or other relaying systems. The SEL-267D relay retains the
twelve most recent event reports. A user may recall any of these reports on command.
Phasor diagrams of the voltages and currents showing prefault, fault, and postfault conditions
can be constructed from the fault report. This accurate information is useful in verifying
short-circuit and load-flow calculations, verifying transmission line constants, and measuring
voltage and current unbalance. It can also be used to check the input connections for proper
phase-sequence rotation and polarity.
This instrument is designed to provide long-term accuracy and availability. Amplitude-
dependent measurements are made with respect to an internal voltage reference which is stable
and precise. Extensive self testing functions monitor the voltage reference. Long-term phase
stability is guaranteed, since all phase-shifting operations are performed by precise time delays
controlled from a quartz crystal oscillator.
1-4
Introduction
SEL-267D/167D Instruction Manual
Date Code 920326
Summary of Contents for SEL-167D
Page 3: ......
Page 6: ......
Page 8: ......
Page 9: ......
Page 10: ......
Page 11: ......
Page 51: ...LOGIC DIAGRAMS Date Code 920326 Specifications SEL 267D 167D Instruction Manual 2 31 ...
Page 52: ...Date Code 920326 Specifications 2 32 SEL 267D 167D Instruction Manual ...
Page 53: ...Date Code 920326 Specifications SEL 267D 167D Instruction Manual 2 33 ...
Page 54: ...Date Code 920326 Specifications SEL 267D 167D Instruction Manual 2 34 ...
Page 88: ...SAMPLE EVENT REPORT ...
Page 114: ......
Page 115: ......