Table of Contents
Advertisement
6.2 STATUS
•
CHANNEL 1(2) STATUS: This represents the receiver status of each channel. If the value is "OK", the 87L current dif-
ferential element is enabled and data is being received from the remote terminal; If the value is "FAIL", the 87L element
is enabled and data is not being received from the remote terminal. If "n/a", the 87L element is disabled.
•
CHANNEL 1(2) LOST PACKETS: Current, timing, and control data is transmitted to the remote terminals in data pack-
ets at a rate of two packets per cycle. The number of lost packets represents data packets lost in transmission; this
count can be reset through the
•
CHANNEL 1(2) LOCAL LOOPBACK STATUS: The result of the local loopback test is displayed here.
•
CHANNEL 1(2) REMOTE LOOPBACK STATUS: The result of the remote loopback test is displayed here.
•
CHANNEL 1(2) LOOP DELAY: Displays the round trip channel delay (including loopback processing time of the
remote relay) computed during a remote loopback test under normal relay operation, in milliseconds (ms).
•
CHANNEL 1(2) ASYMMETRY: The result of channel asymmetry calculations derived from GPS signal is being dis-
played here for both channels if
transmitting direction is less than the delay in the receiving direction; a negative "–" sign indicates the transit delay in
the transmitting direction is more than the delay in the receiving direction. A displayed value of "0.0" indicates that
either asymmetry is not present or can not be estimated due to failure with local/remote GPS clock source.
•
VALIDITY OF CHANNEL CONFIGURATION: The current state of the communications channel identification check,
and hence validity, is displayed here. If a remote relay ID number does not match the programmed number at the local
relay, the "FAIL" value is displayed. The "n/a" value appears if the local relay ID is set to a default value of "0" or if the
87L element is disabled. Refer to
•
PFLL STATUS: This value represents the status of the phase and frequency locked loop (PFLL) filter which uses tim-
ing information from local and remote terminals to synchronize the clocks of all terminals. If
clocks of all terminals are synchronized and 87L protection is enabled. If it is "FAIL", the clocks of all terminals are not
synchronized and 87L protection is disabled. If "n/a", then PFLL is disabled.
At startup, the clocks of all terminals are not synchronized and the PFLL status displayed is "FAIL". It
takes up to 8 seconds after startup for the value displayed to change from "FAIL" to "OK".
NOTE
6
PATH: ACTUAL VALUES
DIGITAL COUNTERS
Counter 1
The present status of the eight digital counters is shown here. The status of each counter, with the user-defined counter
name, includes the accumulated and frozen counts (the count units label will also appear). Also included, is the date and
time stamp for the frozen count. The
PATH: ACTUAL VALUES
SELECTOR SWITCHES
6-8
COMMANDS
CHANNEL ASYMMETRY
SETTINGS
STATUS
DIGITAL COUNTERS
Counter 1
Counter 1
MESSAGE
Counter 1
MESSAGE
YYYY/MM/DD HH:MM:SS
Counter 1
MESSAGE
COUNTER 1 MICROS
STATUS
SELECTOR SWITCHES
SELECTOR SWITCH 1
POSITION: 0/7
SELECTOR SWITCH 2
MESSAGE
POSITION: 0/7
L90 Line Current Differential System
menu.
CLEAR RECORDS
is "Enabled". A positive "+" sign indicates the transit delay in the
SYSTEM SETUP
L90 POWER SYSTEM
DIGITAL COUNTERS Counter 1(8)
ACCUM:
0
FROZEN:
0
FROZEN:
MICROS:
0
value refers to the microsecond portion of the time stamp.
Range: Current Position / 7
Range: Current Position / 7
6 ACTUAL VALUES
section for more information
is "OK", the
PFLL STATUS
6.2.11 DIGITAL COUNTERS
6.2.12 SELECTOR SWITCHES
GE Multilin
Advertisement
Table of Contents
