6-8 L90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUALSTATUS CHAPTER 6: ACTUAL VALUES6CHANNEL 1(2) STATUS — This represents the receiver status of each channel. If the value is “OK,” the 87L current differentialelement is enabled and data is being received from the remote terminal; If the value is “FAIL,” the 87L element is enabledand 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 packets at arate of two packets per cycle. The number of lost packets represents data packets lost in transmission; this count can bereset through the COMMANDS CLEAR RECORDS menu.CHANNEL 1(2) LOCAL LOOPBACK STATUS — The result of the local loopback test displays here.CHANNEL 1(2) REMOTE LOOPBACK STATUS — The result of the remote loopback test displays 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).CHNL 1(2) ASYMMETRY — The result of channel asymmetry calculations derived from GPS signal displays here for bothchannels if CHANNEL ASYMMETRY is “Enabled”. A positive “+” sign indicates that the transit delay in the transmitting directionis less than the delay in the receiving direction; a negative “–” sign indicates that the transit delay in the transmittingdirection is more than the delay in the receiving direction. A displayed value of “0.0” indicates that either asymmetry is notpresent or cannot 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 hencevalidity, displays here. If a remote relay ID number does not match the programmed number at the local relay, the “FAIL”value displays. 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.See the SETTINGS SYSTEM SETUP POWER SYSTEM section for more informationPFLL STATUS — This value represents the status of the phase and frequency locked loop (PFLL) filter that uses timinginformation from local and remote terminals to synchronize the clocks of all terminals. If PFLL STATUS is “OK,” the clocks ofall terminals are synchronized and 87L protection is enabled. If it is “FAIL,” the clocks of all terminals are not synchronizedand 87L protection is disabled. At startup, the clocks of all terminals are not synchronized and the PFLL status displays as“FAIL.” It takes up to eight seconds after startup for the value to change from “FAIL” to “OK.” When the status is “n/a,” thenPFLL is disabled.6.3.12 Digital countersACTUAL VALUES STATUS DIGITAL COUNTERS DIGITAL COUNTERS Counter 1(8)The present status of the eight digital counters displays here. The status of each counter, with the user-defined countername, includes the accumulated and frozen counts (the count units label also appears). Also included, is the date and timestamp for the frozen count. The COUNTER 1 MICROS value refers to the microsecond portion of the time stamp.6.3.13 Selector switchesACTUAL VALUES STATUS SELECTOR SWITCHES DIGITAL COUNTERS Counter 1 Counter 1 ACCUM:0 Counter 1 FROZEN:0 Counter 1 FROZEN:1970/01/01 00:00:00Range: YYYY/MM/DD HH:MM:SS Counter 1 MICROS:0Range: 0 to 4294967295 in steps of 1 SELECTOR SWITCHES SELECTOR SWITCH 1POSITION: 0/7Range: Current Position / 7 SELECTOR SWITCH 2POSITION: 0/7Range: Current Position / 7
