Schweitzer Engineering Laboratories SEL-751 - Table 4.70 LEA Ratio and Phase Correction Settings for Synchronism-Check Voltage; Table 4.71 Time and Date Management Settings

4.172
SEL-751 Relay Instruction Manual Date Code 20170927
Protection and Logic Functions
Global Settings (SET G Command)
The LEA ratio correction factor (RCF) settings—VARCF, VBRCF, VCRCF,
and VSRCF—compensate for irregularities (on a per-phase basis) of voltage
dividers connected between the primary voltage system and the corresponding
LEA inputs. The LEA phase correction (PAC) settings—VAPAC, VBPAC,
VCPAC, and VSPAC—compensate for the phase shift on the corresponding
channels caused by the voltage divider and the shielded cable bringing the
voltages to the SEL-751. Refer to Ratio Correction Factors (RCF) for Voltage
Inputs on page 4.8 for the discussion on the RCF and PAC settings.
Synchrophasor
Measurement
The SEL-751 provides Phasor Measurement Control Unit (PMCU) capabili-
ties when connected to an IRIG-B time source. See Appendix I:
Synchrophasors for the description and Table I . 1 for the settings.
Time and Date
Management Settings
The SEL-751 supports several methods of updating the relay time and date.
For IRIG-B and Phasor Measurement Unit (PMU) synchrophasor applica-
tions, refer to Appendix I: Synchrophasors for the description and Table I.1 for
the settings. For SNTP applications, refer to Simple Network Time Protocol
(SNTP) on page 7.14. For time update from a DNP Master, see Time Synchro-
nization on page D.9.
Table 4.71 shows the time and date management settings that are available in
the Global settings.
Table 4.70 LEA Ratio and Phase Correction Settings for Synchronism-Check
Voltage
Setting Prompt Setting Range
Setting
Name := Factory
Default
VS RATIO CORRECT 0.500–1.500 VSRCF := 1.000
VS ANGLE CORRECT –10.0 to 10.0 deg VSPAC := 0.0
Table 4.71 Time and Date Management Settings
Setting Description Setting Range
Setting Name :=
Fac to ry Default
IRIG-B Control Bits Definition NONE, C37.118 IRIGC := NONE
Offset From UTC –24.00 to 24.00 hours,
rounds up to nearest 0.25
hour
UTC_OFF := 0.00
Month To begin DST OFF, 1–12 DST_BEGM := OFF
Week Of The Month To Begin DST 1–3, L DST_BEGW := 2
Day Of The Week To Begin DST SUN, MON, TUE, WED,
THU, FRI, SAT, SUN
DST_BEGD := SUN
Local Hour To Begin DST 0–23 DST_BEGH := 2
Month To End DST 1–12 DST_ENDM := 11
Week Of The Month To End DST 1–3, L DST_ENDW := 1
Day Of The Week To End DST SUN, MON, TUE, WED,
THU, FRI, SAT, SUN
DST_ENDD := SUN
Local Hour To End DST 0–23 DST_ENDH := 2