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I.L. 40-385.7
a. Using T-connection (with Doble or Multi-Amp Test Unit; refer to B-3 for external terminal
connection and configuration 1.
• V
= 1/2 V
A
• V
= 1/2 V
B
• V
= 3/2 (70) = 105V @ 90° lead
C
Using V
• V
= 15V @ 0°
A
• V
= 15V @ 180°
B
NOTE:
Current (I
The following table is for BC and CA fault tests when the T-connection is used.
b. Using Y-connection
This test is actually for φφG testing (see Figure B-3, configuration 1).
NOTE:
V AN
V BN
V CN
or
V
AN
V
BN
V
CN
For either T or Y connection, using a value of x = 75 ° (lagging), current required to trip:
A-6
@ 0°
F
@ 180°
F
= V
-V
= 30V
F
A
B
) required to trip = 3.33A ± 5%, with an angle of -75 degrees.
A
BC
= 105 ∠90°
V
AN
= 15 ∠0°
V
BN
= 15 ∠180°
V
CN
= 3.33 ∠−75°
I
F
2
1
∠
------ -
=
-- -
V F
2
3
1
2
=
-- -
V F
------ -
2
3
3
×
=
-- -
70
–
V
2
∠
=
17.3
0°
∠
=
17.3
–
120°
∠
=
96.4
120°
CA
= 15 ∠180°
V
AN
= 105 ∠90°
V
BN
= 15 ∠0°
V
CN
= 3.33 ∠−75°
I
F
0°
∠
–
120°
120°
1
2
∠
2
–
-- - V
AN
F
2
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