Schweitzer Engineering Laboratories SEL-751 - Table 5.7 Synchrophasor Measured Values

5.12
SEL-751 Relay Instruction Manual Date Code 20170927
Metering and Monitoring
Metering
Synchrophasor
Metering
You can use the METER PM serial port ASCII command to view the
SEL-751 synchrophasor measurements. There are multiple ways to use the
METER PM command:
➤ As a test tool, to verify connections, phase rotation, and
scaling.
➤ As an analytical tool, to capture synchrophasor data at an exact
time and to compare it with similar data captured in other
phasor measurement unit(s) at the same time.
The METER PM command displays the same set of analog synchrophasor
information, regardless of the global settings PHDATAV, PHDATAI, and
PHCURR. The METER PM command can function even when no serial
ports are sending synchrophasor data.
NOTE: To have th e MET PM xx:yy:zz
response transmitted from a serial
port, the corresponding port must
have the AUTO setting set to YES (Y).
The METER PM command only operates when the SEL-751 is in the IRIG
timekeeping mode, as indicated by Relay Word bit TSOK = logical 1.
Table 5.7 shows the measured values for the METER PM command.
Figure I.7 in Appendix I: Synchrophasors, shows a sample METER PM
command response. You can use the METER PM XX:XX:XXX command to
direct the SEL-751 to display the synchrophasor for an exact specified time, in
24-hour format. For example, entering the command METER PM 14:14:12
results in a response similar to Figure I.7, occurring just after 14:14:12, with
the time stamp 14:14:12.000. Refer to Appendix I: Synchrophasors, for further
details on synchrophasor measurements, settings, C37.118 Protocol, etc.
Remote Analog
Metering
Use remote analog metering to verify the values received from an external
device. The SEL-751 includes 128 remote analog variables. In Appendix C:
SEL Communications Processors, we show how to enter remote analog
settings in an SEL Communications Processor and the SEL-751. Figure 5.14
shows the device response to the METER RA command for the settings in
Appendix C: SEL Communications Processors.
Table 5.7 Synchrophasor Measured Values
Relay Option Meter Values
Currents
(all models)
Currents: IA, IB, IC, IN, I1 (positive-sequence current) magnitudes
(A primary) and phase angles (deg)
Digitals TSOK and SV17–SV32 Relay Word Bit status
Analogs MV29–MV32 Math Variables
a
a
These data are calculated every 25 ms. Only the data that occur at the “Top of the Second”
are used for METER PM responses.
System Frequency (Hz)
Rate-of-change-of-frequency (Hz/Second)
Voltages
(models with
voltage inputs)
Voltage phasors: VA, VB, VC, VS (if VS option is available), and V1
(positive-sequence voltage), magnitudes (V or kV primary) and phase
angles (deg)
NOTE: When METER PM is set for an
exact specified time (time trigger),
the METER PM response shows the time
in UTC time (not local time).