Schweitzer Engineering Laboratories SEL-700G Series, Инструкция по эксплуатации

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4.93
Date Code 20170814 Instruction Manual SEL-700G Relay
Protection and Logic Functions
Group Settings (SET Command)
When a core-balance CT is not available, use the 50G residual overcurrent
elements.
The relay offers two negative-sequence overcurrent elements per winding to
detect phase-to-phase faults, phase reversal, single phasing, and unbalance
load.
Time-Overcurrent Elements
One level of inverse time elements is available for maximum phase, negative-
sequence, residual, and neutral overcurrent. Refer to Table 1.1 and Table 1.2
for the elements available in specific relay models. Table 4.21 through
Table 4.24 show the settings associated with the time-overcurrent elements.
You can select from five U.S. and five IEC inverse characteristics. Table 4.25
and Table 4.26 show the equations for the curves, and Figure 4.62 through
Figure 4.71 show the curves. The curves and equations shown do not account
for constant time adder and minimum response time (settings 51_CT and
51_MR respectively, each assumed equal to zero). Use the 51_CT if you want
to raise the curves by a constant time. Also, you can use the 51_MR if you
want to ensure that the curve times no faster than a minimum response time.
You can use appropriate SEL
OGIC
control equations (for example, when
51NTC := IN401, the 51N element operates only if IN401 is asserted) to
torque control each element. You can also control the elements by directional
elements depending on the relay model number (refer to Table 1.2).
Directional elements are described later in this section.
Table 4.19 Residual Overcurrent Settings
Setting Prompt Setting Range
Setting Name :=
Factory Default
a
a
m = X or Y.
RES IOC LEVEL OFF, 0.50–96.00 A
b
b
Setting ranges shown are for 5 A nominal CT rating. Divide by 5 for 1 A CTs.
50Gm1P := OFF
RES IOC DELAY 0.00–400.00 s 50Pm1D := 0.50
RES IOC TRQCTRL SEL
OGIC
50Pm1TC := 1
RES IOC LEVEL OFF, 0.50–96.00 A
b
50Gm2P := OFF
RES IOC DELAY 0.00–400.00 s 50Pm2D := 0.50
RES IOC TRQCTRL SEL
OGIC
50Pm2TC := 1
Table 4.20 Negative-Sequence Overcurrent Settings
Setting Prompt Setting Range
Setting Name :=
Factory Default
a
a
m = X or Y.
NSEQ IOC LEVEL OFF, 0.50–96.00 A
b
b
Settings ranges shown are for 5 A nominal CT rating. Divide by 5 for 1 A CTs.
50Qm1P := OFF
NSEQ IOC DELAY 0.00–400.00 s 50Qm1D := 0.50
NSEQ IOC TRQCTRL SEL
OGIC
50Qm1TC := 1
NSEQ IOC LEVEL OFF, 0.50–96.00 A
b
50Qm2P := OFF
NSEQ IOC DELAY 0.00–400.00 s 50Qm2D := 0.50
NSEQ IOC TRQCTRL SEL
OGIC
50Qm2TC := 1