I.L. 40-385.5
A-6
• GTC
= 24
NOTE: The note in Step 20 applies to the GB
test. The GB can be set to directional
ground overcurrent. For loss-of-poten-
tial condition, GB will be converted to
non-directional, automatically, regard-
less of the GDIR=YES setting.
Using Figure A-1, apply A-G fault of 4.1A to MDAR.
Trip time is determined as follows:
(T
MSEC
) =
where
(3I
OF
is zero sequence fault current.)
(T
MSEC
) =
T
MSEC
=
1073 msec
=
1.073 sec
±
5 % to trip
For values of 3I
0
between 1.0 and 1.5, the following
equation would apply:
(T
MSEC
) =
The following equation can be used to calculate the
trip time for all CO curves from CO-2 to CO-11:
T(sec) =
T(sec) =
where
GBPU = Pickup current setting (0.5 to 4.0A).
GTC
= Time curve dial setting (1 to 63).
T
o
, K, C, P and R are constants, and are shown in
Table A-2.
Step 24. For a Zero Sequence Directional unit (DI-
RU = ZSEQ), the tripping direction of MDAR is:
the angle of 3I
0
leads 3V
0
b30
°
and
+210
°
. Change the setting of GDIR to “YES”. Ap-
ply AG fault as shown in preceding Step 10, Fig-
ure A-1. The relay should trip at the following
angles:
• +28
°
• -60
°
(
±
88
°
)
• -148
°
The relay should
not trip at the angles of:
• +32
°
• +120
°
(
±
88
°
)
• -152
°
For a Negative Sequence Directional Unit (DIRU =
NSEQ), the tripping direction of MDAR is: I
2
leads V
2
by a value b8
°
and +188
°
. The
relay should trip at the following angles:
• +3
°
• -82
°
(
±
85
°
)
• -167
°
The relay should not trip at the angles of:
• +13
°
• +98
°
(
±
85
°
)
• +183
°
Step 25. For a dual polarizing ground directional
unit (DIRU = DUAL) test, connect the test circuit
shown in Figure A -4; apply Lp 1.0A
to
terminals 12 (+) and 11(-), and apply a balanced
3-phase voltage (70V) to V
a
, V
b
, V
c
, and V
n
. Ap-
ply Ia = 4A to terminals 6(+) and 5(-).
NOTE: In order to eliminate the voltage polariz-
ing effect, make sure the voltages are
finely balanced so that 3V0 is less than
3.0 volt. If it is impossible to obtain
3V
0
< 3V, set V
a
= V
b
= V
c
= 0
for the following tests.
The relay should trip at the following angles:
• -3
°
• -90
°
(
±
87
°
)
• -177
°
The relay should not trip at the following angles:
• +3
°
478
4122
3I
0
1.27
–
------------------------
+
GTC
24
------------
3I
0
3I
OF
GBPU
-----------------
=
478
4122
4.1/0.5 -1.27
------------------------------
+
24
24
------
9200
(
)
3I
0
1
–
-----------------
GTC
24
------------
×
CO
8 only
–
(
)
T
0
K
3I
0
C
–
(
)
p
--------------------------
+
GTC
24 000
,
------------------
for 3I
0
1.5
≥
(
×
R
I
0
1
–
)
------------------
GTC
24 000
,
------------------
×
for 1
3I
0
1.5
<
<
(
3I
0
3I
OF
GBPU
-----------------
=
90
°
–
∠
Содержание MDAR
Страница 84: ......
Страница 88: ...I L 40 385 5 A 16 Figure A 1 Test Connection for Single Phase to Ground Faults Sheet 1 of 4 1502B51 Sub 1 ...
Страница 89: ...I L 40 385 5 A 17 Figure A 2 Test Connection for Three Phase Faults 1502B51 Sub 1 Sheet 2 of 4 ...
Страница 90: ...I L 40 385 5 A 18 Figure A 3 Test Connection for Phase to Phase Faults 1502B51 Sub 1 Sheet 3 of 4 ...
Страница 96: ......
Страница 98: ...I L 40 385 5 A 26 I L 40 385 5 A 26 I L 40 385 5 A 26 Figure 5 MDAR REL 300 Relay Assembly sub 3 1502B21 ...
Страница 101: ......
Страница 102: ......
Страница 104: ......
Страница 105: ...I L 40 385 5 A 33 I L 40 385 5 A 33 I L 40 385 5 A 33 Figure 15 MDAR REL 300 Zone 1 Trip Logic sub 1 9659A66 ...
Страница 106: ...I L 40 385 5 A 34 I L 40 385 5 A 34 I L 40 385 5 A 34 Figure 16 MDAR REL 300 Zone 2 Trip Logic sub 1 9659A67 ...
Страница 107: ...I L 40 385 5 A 35 I L 40 385 5 A 35 I L 40 385 5 A 35 Figure 17 MDAR REL 300 Zone 3 Trip Logic sub 1 1504B04 ...
Страница 111: ......
Страница 112: ...I L 40 385 5 A 40 I L 40 385 5 A 40 I L 40 385 5 A 40 Figure 25 Load Loss Accelerated Trip Logic sub 2 1504B29 ...
Страница 116: ......
Страница 118: ...I L 40 385 5 A 46 I L 40 385 5 A 46 I L 40 385 5 A 46 Figure 35 Power Reversal sub 1 9654A17 ...
Страница 119: ...I L 40 385 5 A 47 I L 40 385 5 A 47 I L 40 385 5 A 47 Figure 36 Reverse Block Logic sub 1 9659A73 ...
Страница 120: ...I L 40 385 5 A 48 I L 40 385 5 A 48 I L 40 385 5 A 48 Figure 37 Unequal Pole Closing on Fault sub 1 9654A29 ...
Страница 121: ...I L 40 385 5 A 49 I L 40 385 5 A 49 I L 40 385 5 A 49 Figure 38 Simplified MDAR Version 2 60 SPT Logic sub 4 1504B32 ...
Страница 122: ...I L 40 385 5 A 50 I L 40 385 5 A 50 I L 40 385 5 A 50 Figure 39 MDAR Block Diagram sub 1 1611C12 ...
Страница 123: ......
Страница 124: ......
Страница 125: ......