10.9
Date Code 20081022
Instruction Manual
SEL-787 Relay
Testing and Troubleshooting
Commissioning Tests
Figure 10.6
Wye Voltage Source Connections
Step 3. Using the front-panel
SET/SHOW
or the serial port
SHOW
command, record the CTR
n
(where
n
= VIWDG setting), PTR,
and PHROT setting values.
Step 4. Apply the current and voltage quantities shown in Column 1 of
Values are given for PHROT := ABC and PHROT := ACB.
Step 5. Use the front-panel
METER
function or the serial port
MET
command to verify the results.
Delta-Connected Voltages
Perform the following steps to test delta-connected voltages:
Step 1. Connect the current source to the relay, as shown in
(VIWDG = 1) or
(VIWDG = 2).
Step 2. Connect the voltage source to the relay, as shown in
. Make sure that DELTA_Y := DELTA.
SEL-787
E01
E02
E03
E04
Voltage
Test
Source
VA
VB
VC
VN
Table 10.5
Power Quantity Accuracy—Wye Voltages
a
Applied Currents and Voltages
Real Power
(kW)
Reactive Power (kVAR)
Power Factor
(pf)
PHROT := ABC
IAW
n
= 2.5
∠−26
IBW
n
= 2.5
∠−
146
ICW
n
= 2.5
∠
+94
Expected:
P = 0.4523 • CTR
n
• PTR
Expected:
Q = 0.2211 • CTR
n
• PTR
Expected:
pf = 0.90 lag
VA = 67
∠
0
VB = 67
∠−
120
VC = 67
∠
+120
Measured:
Measured:
Measured:
PHROT := ACB
IAW
n
= 2.5
∠−
26
IBW
n
= 2.5
∠
+94
ICW
n
= 2.5
∠−
146
Expected:
P = 0.4523 • CTR
n
• PTR
Expected:
Q = 0.2211 • CTR
n
• PTR
Expected:
pf = 0.90 lag
VA = 67
∠
0
VB = 67
∠+
120
VC = 67
∠−
120
Measured:
Measured:
Measured:
a
n = VIWDG setting
Summary of Contents for SEL-787
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