
Date Code 20011205
Distance, Overcurrent, Voltage,
3-21
and Synchronism Check Elements
SEL-311B Instruction Manual
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
1.2
2
3
4
5
6
7
8
9
10
Applied Current (Multiples of Pickup Setting)
Reset Time (Cycles)
Maximum
Minimum
Figure 3.15: SEL-311B Relay Nondirectional Instantaneous Overcurrent Element Reset
Time Curve
Residual Ground Instantaneous/Definite-Time Overcurrent Elements
Three levels of residual ground instantaneous/definite-time overcurrent elements are available.
The different levels are enabled with the E50G enable setting, as shown in Figure 3.16.
All residual ground instantaneous/definite-time overcurrent elements are available for use in any
user-defined tripping or control scheme.
To understand the operation of Figure 3.16, follow the explanation given for Figure 3.13 in the
preceding
Phase Instantaneous/Definite-Time Overcurrent Elements
subsection, substituting
residual ground current I
G
(I
G
= 3I
0
= I
A
+ I
B
+ I
C
) for phase currents and substituting like settings
and Relay Word bits.
In Figure 3.16 Levels 1 and 2 67G
n
elements have their directional control fixed forward. Level
3 has selectable forward and reverse directional controls. See Figure 4.12 in
Section 4: Loss-of-
Potential, CCVT Transient Detection, Load-Encroachment, and Directional Element Logic
for
more information on directional control.
Содержание SEL-311B
Страница 6: ......
Страница 8: ......
Страница 10: ......
Страница 24: ......
Страница 26: ......
Страница 122: ......
Страница 124: ......
Страница 138: ......
Страница 168: ......
Страница 172: ......
Страница 254: ......
Страница 282: ......
Страница 306: ......
Страница 348: ......
Страница 364: ......
Страница 366: ......
Страница 448: ......
Страница 460: ......
Страница 466: ......
Страница 476: ......
Страница 482: ......
Страница 494: ......
Страница 500: ......
Страница 522: ......
Страница 526: ......
Страница 528: ......
Страница 534: ......
Страница 536: ......
Страница 550: ......
Страница 570: ......
Страница 586: ......
Страница 600: ......