Schweitzer Engineering Laboratories SEL-787 - Figure 10.2 Three-Phase Wye AC Connections; Figure 10.3 Three-Phase Open-Delta AC Connections

10.5
Date Code 20081022 Instruction Manual SEL-787 Relay
Testing and Troubleshooting
Commissioning Tests
c. If you set the relay to accept delta voltages
(DELTA_Y := DELTA), set the current and/or voltage
phase angles as shown in Figure 10.3.
Figure 10.2 Three-Phase Wye AC Connections
Figure 10.3 Three-Phase Open-Delta AC Connections
Step 12. Apply rated current (1 A or 5 A).
Step 13. If the relay is equipped with voltage inputs, apply rated voltage
for your application.
Step 14. Use the front-panel
METER > Fundamental function or serial
port METER command to verify that the relay is measuring
the magnitude and phase angle of both voltage and current
+120˚
–120˚
V
C
V
B
V
C
V
A
PHROT := ABC
+120˚
–120˚
PHROT := ACB
V
B
V
A
When setting PHROT := ABC, set angle V
A
= angle I
A
= 0˚
set angle V
B
= angle I
B
= —120˚
set angle V
C
= angle I
C
= 120˚
When setting PHROT := ACB, set angle V
A
= angle I
A
= 0˚
set angle V
B
= angle I
B
= 120˚
set angle V
C
= angle I
C
= —120˚
60˚
V
AB
V
CB
PHROT := ABC
60˚
V
AB
V
CB
PHROT := ACB
When setting PHROT := ABC, set angle I
A
= 0˚
set angle I
B
= —120˚
set angle I
C
= 120˚
set angle V
AB
= +30˚
set angle V
CB
= +90˚
When setting PHROT := ACB, set angle I
A
= 0˚
set angle I
B
= 120˚
set angle I
C
= —120˚
set angle V
AB
= —30˚
set angle V
CB
= —90˚