Real Time Clock - GE L30 Instruction Manual

5.2 PRODUCT SETUP
a) MAIN MENU

PATH: SETTINGS PRODUCT SETUP
 REAL TIME
 CLOCK
The relay contains a real time clock (RTC) to create timestamps for communications protocols as well as for historical data,
such as event records and oscillography. When the relay restarts, the RTC initializes from an onboard battery-backed
clock, which has the same accuracy as an electronic watch, approximately ±1 minute per month (~23 ppm). Once the RTC
is synchronized with the Precision Time Protocol (PTP), IRIG-B, or SNTP, its accuracy approaches that of the synchroniz-
ing time delivered to the relay. When the L30/L90 channel asymmetry function is used, the relay's real time clock must be
5
synchronized to an external time source using PTP or IRIG-B, typically from a global positioning system (GPS) receiver.
The
SYNCHRONIZING SOURCE
able external time sources synchronizes the RTC and the synchrophasor clock. A setting of None causes the RTC and the
synchrophasor clock to free-run. A setting of PP/IRIGB/PTP/SNTP, IRIGB/PP/PTP/SNTP, or PP/PTP/IRIGB/SNTP causes
the relay to track the first source named that is enabled and operational, or free-run if none of these are available. Here, PP
means a time source that is strictly compliant with PP, PTP means a time source that is not strictly compliant with PP. When
a time source fails or recovers, the relay automatically transfers synchronization as required by this setting.
See the 
COMMANDS
The
REAL TIME CLOCK EVENTS
records the RTC time before the adjustment.
To enable IRIG-B synchronization, the input
synchronization can be disabled by making this setting None.
To configure and enable PTP and/or SNTP, or to set local time parameters (for example time zone, daylight savings), use
the following sections.
5-58


REAL TIME CLOCK

SYNCRONIZING SOURCE:
None
REAL TIME CLOCK
MESSAGE
EVENTS: Disabled
IRIG-B SIGNAL TYPE:
MESSAGE
None
 PRECISION TIME
MESSAGE
 PROTOCOL (1588)
 SNTP PROTOCOL
MESSAGE

 LOCAL TIME
MESSAGE

setting configures the priority sequence that the relay uses to determine which of the avail-
menu section of this manual to manually set the RTC.
SET DATE AND TIME
setting allows changes to the date and/or time to be captured in the event record. The event
IRIG-B SIGNAL TYPE
L30 Line Current Differential System
Range: None, PP/IRIG-B/PTP/SNTP, IRIG-B/PP/PTP/
SNTP, PP/PTP/IRIG-B/SNTP
Range: Enabled, Disabled
Range: None, DC Shift, Amplitude Modulated
See below
See below
See below
must be set to DC Shift or Amplitude Modulated. IRIG-B
5 SETTINGS
5.2.6 REAL TIME CLOCK
GE Multilin