GE UR Series L90, Instruction Manual

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GE Multilin L90 Line Current Differential System 5-55
5 SETTINGS 5.2 PRODUCT SETUP
5
c) LOCAL TIME
PATH: SETTINGS

PRODUCT SETUP

REAL TIME CLOCK

LOCAL TIME
The UR device maintains two times: local time and Universal Coordinated Time (UTC). Local time can be provided by IRIG-
B signals. UTC time is provided by SNTP servers.
The real-time clock (RTC) and communication protocol times are not correct unless Local Time is configured for the current
location. When the RTC is synchronized with IRIG-B, Local Time must be configured for the current location or else the
timestamps may not be accurate. Furthermore, times reported in historical records and communication protocols may be
incorrect if the Local Time setting is not configured properly.
The
LOCAL TIME OFFSET FROM UTC
setting is used to specify the local time zone offset from UTC (Greenwich Mean Time) in
hours. Time zones in the eastern hemisphere have positive values; time zones in the western hemisphere have negative
values. A value of zero causes the relay to use UTC for local time. This setting has two uses. When the system RTC is syn-
chronized with a communications protocol providing only local time or it is free-running, the offset setting is used to calcu-
late UTC from the local time these provide. When the RTC is synchronized with a communications protocol providing only
UTC (such as PTP or SNTP), the time offset setting is used to determine local time from the UTC provided. PTP
ALTERNATE_TIME_OFFSET_INDICATOR TLVs are not used to calculate local time. When a communications protocol
other than PTP provides UTC to local time offset (meaning IRIG-B), that offset is used instead of the local time and daylight
time settings.
The
DAYLIGHT SAVINGS TIME (DST)
settings can be used to allow the relay to follow the DST rules of the local time zone.
Note that when IRIG-B time synchronization is active, the local time in the IRIG-B signal contains any daylight savings time
offset and so the DST settings are ignored.

LOCAL TIME

LOCAL TIME OFFSET
FROM UTC:
0.0 hrs
Range: –24.0 to 24.0 hrs in steps of 0.5
MESSAGE
DAYLIGHT SAVINGS
TIME: Disabled
Range: Disabled, Enabled
MESSAGE
DST START MONTH:
January
Range: January to December (all months)
MESSAGE
DST START DAY:
Sunday
Range: Sunday to Saturday (all days of the week)
MESSAGE
DST START DAY
INSTANCE: First
Range: First, Second, Third, Fourth, Last
MESSAGE
DST START HOUR:
2
Range: 0 to 23
MESSAGE
DST STOP MONTH:
January
Range: January to December (all months)
MESSAGE
DST STOP DAY:
Sunday
Range: Sunday to Saturday (all days of the week)
MESSAGE
DST STOP DAY
INSTANCE: First
Range: First, Second, Third, Fourth, Last
MESSAGE
DST STOP HOUR:
2
Range: 0 to 23