Sel SEL-421 - View Synchrophasors by Using the MET PM Command

R.7.24
SEL-421 Relay Reference Manual Date Code 20111215
Synchrophasors
View Synchrophasors by Using the MET PM Command
View Synchrophasors by Using the MET PM
Command
The MET PM serial port ASCII command may be used to view the SEL-421
synchrophasor measurements. See METER on page R.9.28 for general
information on the MET command.
There are multiple ways to use the MET 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, in order to compare it with similar data captured in other
phasor measurement unit(s) at the same time
➤ As a method of periodically gathering synchrophasor data
through a communications processor
The MET PM command displays the same set of analog synchrophasor
information, regardless of the Global settings MFRMT, PHDATAV,
PHDATAI, and PHCURR. The MET PM command can function even when
no serial ports are sending synchrophasor data—it is unaffected by serial port
setting PROTO.
The MET PM command will only operate when the SEL-421 is in the HIRIG
timekeeping mode, as indicated by Relay Word bit TSOK = logical 1.
Figure 7.13 shows a sample MET PM command response. The
synchrophasor data is also available via the HMI > Meter & Control menu in
ACSELERATOR QuickSet, and has a similar format to Figure 7.13.
The MET PM time command can be used to direct the SEL-421 to display the
synchrophasor for an exact specified time, in 24-hour format. For example,
entering the command MET PM 14:14:12 will result in a response similar to
Figure 7.13 occurring just after 14:14:12, with the time stamp
14:14:12.000000.
V1LPMMD Aligned local positive-sequence voltage
magnitude
kV
a
V1LPMAD Aligned local positive-sequence voltage
angle
degrees
V1LPMRD Aligned local positive-sequence voltage real
component
kV
a
V1LPMID Aligned local positive-sequence voltage
imaginary component
kV
a
SODPMD Second-of-day for all aligned data Seconds
FOSPMD Fraction-of-second for all aligned data Seconds
FREQPMD Aligned local system frequency Hz
DFDTD Aligned local rate-of-change of frequency Hz/s
a
Primary value of measurement.
Table 7.14 Synchrophasor Aligned Analog Quantities (Sheet 3 of 3)
Name Description Units