10-10 Testing and Troubleshooting Date Code 20080110
SEL-387E Instruction Manual
Voltage Metering
Step 1. Purpose: Connect simulated power system secondary voltage sources to the relay.
Method: Connect a source of variable three-phase voltage to the relay as shown in
Figure 10.5. Set the voltage sources to deliver 67 Volts with A-phase at
0 degrees, B-phase lagging A-phase by 120 degrees, and C-phase
leading A-phase by 120 degrees.
Voltage Source
VA VB VC VN
VA VB VC
Z19 Z20 Z21
VN Z22
SEL-387E
Partial
M3 87E039
Figure 10.5: Voltage Test Connection
Step 2. Purpose: Verify correct voltage levels.
Method: Turn relay power on, and use the METER command to measure the
voltages applied in Step 1. With applied voltages of 67 Volts per phase
and a voltage transformer ratio of 2000:1 (SHO PTR <Enter> displays
the PT ratios, <Ctrl + X> cancels scrolling), the displayed line voltages
should be the applied voltage, 134 kV ±2 kV and ±5% of applied voltage
times PTR.
Step 3. Purpose: Verify phase rotation.
Method: Verify that residual (VRWx) and negative-sequence (3V2Wx) quantities
are approximately zero. If VRWx equals three times the applied voltage,
then all three phases have the same angle. If 3V2Wx equals three times
the applied voltage, then the phase rotation is reversed.
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