Sel 551 - Retrieving Full Length Standard Event Reports

7.4
SEL-551 Relay Instruction Manual Date Code 20110408
Standard Event Reports and SER
Standard 15-Cycle Event Reports
Currents
The Currents (A pri), ABCNGQ: field shows the currents present in the event
report row containing the maximum phase current. The listed currents are:
➤ Phase (A = channel IA, B = channel IB, C = channel IC)
➤ Neutral (N = channel IN)
➤ Calculated residual (G = 3I
0
; calculated from channels IA, IB,
and IC)
➤ Negative-sequence (Q = 3I
2
; calculated from channels IA, IB,
and IC)
Retrieving Full-
Length Standard
Event Reports
The latest 20 standard 15-cycle (full-length) event reports are stored in
nonvolatile memory. Any given event report has four different ways it can be
displayed, depending on the particular serial port command issued to the relay.
The command choices are shown below. The n parameter refers to the event
report number (n = 1–20), with n = 1 being the most recent event report and
n = 20 being the oldest event report.
If no numeric n parameter is entered with the serial port command, the most
recent event report (n = 1) is displayed.
If an event report is requested which does not exist, the relay responds:
Invalid Event
Ta b le 7 . 1 Even t Ty pe s
Event Event Triggered by:
TRIP Assertion of Relay Word bit TRIP
ER1 SEL
OGIC control equations setting ER1
ER2 SEL
OGIC control equations setting ER2
TRIG Execution of TRIGGER serial port command
PULSE Execution of PULSE serial port command
Serial Port
Command
Format
EVENT n Event report n displayed with rows
of information each quarter (1/4) cycle.
EVENT C n Digital data are added at the end of the
quarter (1/4) cycle resolution event report n.
EVENT L n Event report n displayed with rows of information each 1/8 cycle. See
Figure 7.2 for an example of an 1/8-cycle resolution event report.
EVENT L C n Digital data are added at the end
of the 1/8-cycle resolution event report n.
EVENT R n Event report n displayed with 16 cycles
of raw (unfiltered) analog information in 1/16-cycle resolution.
EVENT R C n Digital Data are added at the end of the
1/16-cycle resolution raw event report n with 1/8-cycle resolution.