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

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4.108
SEL-700G Relay Instruction Manual Date Code 20170814
Protection and Logic Functions
Group Settings (SET Command)
logic points are routed to the different levels of overcurrent protection by the
level direction settings DIR1 and DIR2.
Table 4.33 shows the overcurrent elements that are controlled by each level
direction setting. Note in Table 4.33 that all the time-overcurrent elements
(51_T elements) are controlled by the DIR1 level direction setting.
If a level direction setting (for example, DIR1) is set as follows,
DIR1 := N (nondirectional)
then the corresponding Level 1 directional control outputs in Figure 4.83 and
Figure 4.84 assert to logical 1. The referenced Level 1 overcurrent elements in
Figure 4.83 and Figure 4.84 are then not controlled by the directional control logic.
See the beginning of Directional Control Settings on page 4.121 for a
discussion on the operation of level direction settings DIR1 and DIR2 when
the directional control enable setting EDIR is set to EDIR := N.
In some applications, level direction settings DIR1 and DIR2 are not flexible
enough in assigning the necessary direction for certain overcurrent elements.
Directional Control Provided by Torque Control Settings on page 4.133
describes how to avoid this limitation for special cases.
Figure 4.74 Internal Enables (DIRQE and DIRQGE) Logic for
Negative-Sequence Voltage-Polarized Directional Elements
q
From Figure 4.120
w
From Figure 4.75
e
To Figure 4.77 and Figure 4.86
r
To Figure 4.86
t
To Figure 4.77, Table 4.27 and Table 4.28
|3I
2
|
|I
2
|
a2 • |I
1
|
k2 • |I
0
|
|I
2
|
Setting
Settings
50QFP
50QRP
50QR
50QF
DIRVE
DIRIE
Setting
DIRQE
(Internal Enable)
"Q" Listed in
Setting ORDER
Setting Enable
DIRQGE
(Internal Enable)
(I
0
= I
G/3
)
Loss-of-Potential
Relay
Word Bit
Outputs
LOP
Relay
Word
Bit
Relay
Word
Bits
1
2
3
4
5