Schweitzer Engineering Laboratories SEL-700G Series, Instruction Manual

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4.177
Date Code 20170814 Instruction Manual SEL-700G Relay
Protection and Logic Functions
Group Settings (SET Command)
Set VPULSEI to define an interval for the VRAISE and VLOWER pulses.
Make sure that the interval setting is greater than the time necessary for the
generator voltage to stabilize after a control pulse is applied. This prevents the
relay from overshooting the target magnitude by prematurely applying the
next control pulse. Refer to the exciter/voltage regulator data sheet for
information to properly set the VADJRATE, VPLSMIND, VPLSMAXD, and
VPULSEI settings.
As the generator voltage magnitude gets closer to the target magnitude, the
correction pulses get shorter to prevent hunting and stop when voltage
magnitude is within an acceptable window. Typically, this creates an
acceptable voltage magnitude condition for the synchronism-check function
to assert Relay Word bit 25C and initiate generator breaker closing.
Synchroscope
A
C
SEL
ERATOR
QuickSet SEL-5030 Software provides a synchroscope
display when connected to an SEL-700G Relay. See Figure 4.118 for a sample
display. Refer to Synchroscope in Section 3: PC Software for more
information on this screen.
Figure 4.118 Synchroscope
Autosynchronism and Synchronism-Check Reports
The SEL-700G Relay triggers and saves the generator autosynchronism report
on the rising edge of Relay Word bit GSRTRG. Refer to Table 4.96 for the
GRSTRG SEL
OGIC
control equation setting and the rest of the settings
associated with the autosynchronism report. You may also use the ASCII
command GST (at Access Level 1 or higher) to trigger the generator
autosynchronism report data acquisition (see Section 7: Communications,
GST Command (Trigger GSR) on page 7.30). See Figure 4.119 for a sample
graphical display of the autosynchronism report.
This report can be viewed using the compressed ASCII command CGSR. The
list of all the available autosynchronism reports can be viewed using the
command GSH. Refer to Section 7: Communications, CGSR Command
(Generator Autosynchronism Report) on page 7.23 and GSH Command on
page 7.29 for more information on the commands CGSR and GSH. For more
IMPORTANT:
The synchroscope
display in QuickSet is only intended
for visualization and is not
recommended for the use of closing
the breaker manually for
synchronization while looking at the
graphical scope.