GE UR Series L90 Instruction Manual page 577

9 THEORY OF OPERATION
Table 9–9: PHASE DISTANCE INPUT SIGNALS FOR DELTA-WYE TRANSFORMERS
TRANSFORMER LOOP
CONNECTION
Dy9 AB
BC
CA
Dy11 AB
BC
CA
Table 9–10: PHASE DISTANCE INPUT SIGNALS FOR WYE-DELTA TRANSFORMERS
TRANSFORMER LOOP
CONNECTION
Yd1 AB
BC
CA
Yd3 AB
BC
CA
Yd5 AB
BC
CA
Yd7 AB
BC
CA
GE Multilin
9.4 PHASE DISTANCE APPLIED TO POWER TRANSFORMERS
CURRENT
TRANSFORMATION
I 3I
AB_21P C
I 3I
BC_21P A
I 3I
CA_21P B
I 3I
AB_21P B
I 3I
BC_21P C
I 3I
CA_21P A
CURRENT
TRANSFORMATION
1
------ - 2I  
I I I
AB_21P A B C
3
1
------ - 2I  
I I I
BC_21P B A C
3
1
------ - 2I  
I I I
CA_21P C A B
3
1
------ - I  
I I 2I
AB_21P A B C
3
1
------ - I  
I I 2I
BC_21P B C A
3
1
 
------ - I
I I 2I
CA_21P A C B
3
1
 
------ - 2I
I I I
AB_21P B A C
3
1
 
------ - 2I
I I I
BC_21P C A B
3
1
 
------ - 2I
I I I
CA_21P A B C
3
1
 
------ - I
I I 2I
AB_21P B C A
3
1
 
I ------ - I I 2I
BC_21P A C B
3
1
 
I ------ - I I 2I
CA_21P A B C
3
L90 Line Current Differential System
VOLTAGE
TRANSFORMATION
1
------ - V  
V V
AB_21P CA BC
3
1
------ - V  
V V
BC_21P AB CA
3
1
------ - V  
V V
CA_21P BC AB
3
1
 
------ - V
V V
AB_21P AB BC
3
1
 
------ - V
V V
BC_21P BC CA
3
1
 
------ - V
V V
CA_21P CA AB
3
VOLTAGE
TRANSFORMATION
V 3V
AB_21P A
V 3V
BC_21P B
V 3V
CA_21P C
V 3V
AB_21P C
V 3V
BC_21P A
V 3V
CA_21P B
V 3V
AB_21P B
V 3V
BC_21P C
V 3V
CA_21P A
V 3V
AB_21P A
V 3V
BC_21P B
V 3V
CA_21P C
9
9-31