Schweitzer Engineering Laboratories SEL-311C, Instruction Manual

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4.22
SEL-311C Relay Instruction Manual
Date Code 20060320
Loss-of-Potential, CCVT Transient Detection, Load-Encroachment, and Directional Element Logic
Directional Control Settings
Most communications-assisted trip schemes set with Zone 3/ Level 3 element
direction reverse (DIR3 = R).
ORDER—Ground Directional Element Priority Setting
Setting Range:
Q (Negative-sequence voltage-polarized directional element)
V (Zero-sequence voltage-polarized directional element)
I (Channel IP current-polarized directional element)
Setting ORDER can be set with any combination of Q, V, and I. The order in
which these directional elements are listed determines the priority in which
they operate to provide Best Choice Ground Directional logic control. See
Figure 4.8 .
For example, if setting:
ORDER = QV
then the first listed directional element (Q = negative-sequence voltage-
polarized directional element; see
Figure 4.9 ) is the first priority directional
element to provide directional control for the ground distance and residual
ground overcurrent elements.
If the negative-sequence voltage-polarized directional element is not operable
(i.e., it does not have sufficient operating quantity as indicated by its internal
enable, 32QGE, not being asserted), then the second listed directional element
(V = zero-sequence voltage-polarized directional element; see
Figure 4.10 )
provides directional control for the ground distance and residual ground
overcurrent elements.
Another example, if setting:
ORDER = V
then the zero-sequence voltage-polarized directional element (V = zero-
sequence voltage-polarized directional element; see
Figure 4.10 ) provides
directional control for the ground distance and residual ground overcurrent
elements all the time.
Setting ORDER can be set with any element combination (e.g.,
ORDER = IQV, ORDER = QVI, ORDER = IV, ORDER = VQ, ORDER = I,
ORDER = Q).
If ground quadrilateral distance elements are used, the first entry in the
ORDER setting should be as shown in
Table 4.3 .
DIR3 = F or R M3P ( Figure 3.6 )
M3PT ( Figure 3.16 )
Z3G ( Figure 3.9 )
Z3GT ( Figure 3.16 )
67G3 ( Figure 3.22 )
67G3T ( Figure 3.22 )
67Q3 ( Figure 3.23 )
67Q3T ( Figure 3.23 )
DIR4 = F or R M4P ( Figure 3.6 )
M4PT ( Figure 3.16 )
Z4G ( Figure 3.9 )
Z4GT ( Figure 3.16 )
67G4 ( Figure 3.22 )
67G4T ( Figure 3.22 )
67Q4 ( Figure 3.23 )
67Q4T ( Figure 3.23 )
Table 4.2 Elements Controlled by Zone/Level Direction Settings (Corresponding Overcurrent and Directional
Element Figure Numbers in Parentheses) (Sheet 2 of 2)
Level
Direction
Settings
Phase Distance Ground Distance Residual Ground Negative-Sequence