9424200996 66-5
BE1-11m Phase Current Differential (87) Test
Step 10: To test the Restraint Slope 1 setting, connect two balanced three-phase current sources to the
BE1-11m in ABC rotation: 3.0∠0°, 3.0∠–120°, 3.0∠120° amps to terminals D1 through D6 and
3.0∠180°, 3.0∠60°, 3.0∠–60° amps to terminals F1 through F6 (1.5x tap).
Step 11: Slowly increase the A-phase current in CT circuit 1 or 2 until OUT2 closes and record the
pickup. This should occur at 3.67 A ±0.07 A. Verify that there is an 87A target on the front-panel
display.
Step 12: Reset to the current levels in step 10 and reset all targets.
Step 13: Slowly decrease the A-phase current in CT circuit 1 or 2 until OUT2 closes and record the
pickup. This should occur at 2.46 A ±0.05 A. Verify that there is an 87A target on the front-panel
display.
Step 14: To test the Restraint Slope 2 setting, connect two balanced three-phase current sources to the
BE1-11m in ABC rotation:6.5∠0°, 6.5∠–120°, 6.5∠120° amps to terminals D1 through D6 and
6.5∠180°, 6.5∠60°, 6.5∠–60° amps to terminals F1 through F6 (3.25x tap).
Step 15: Slowly increase the A-phase current in CT circuit 1 or 2 until OUT2 closes and record the
pickup. This should occur at 8.25 A ±0.17 A. Verify that there is an 87A target on the front-panel
display.
Step 16: Reset to the current levels in step 14 and reset all targets.
Step 17: Slowly decrease the A-phase current in CT circuit 1 or 2 until OUT2 closes and record the
pickup. This should occur at 5.32 A ±0.11 A. Verify that there is an 87A target on the front-panel
display.
Step 18: (Optional.) Repeat steps 1 through 17 for the B-phase and C-phase current inputs.
Step 19: (Optional.) Repeat steps 1 through 18 for settings group 1, 2, and 3.
Timing Verification (Maximum or Average Restraint)
Step 1: Use BESTCOMSPlus to verify the operational settings in Table 66-1 (Maximum) or 2 (Average)
and logic in Figure 66-1. Reset all targets.
Step 2: Prepare to monitor the 87 timings. Timing accuracy is verified by measuring the elapsed time
between OUT2 (pickup) and OUT1 (trip) closing.
Step 3: Connect two balanced three-phase current sources to the BE1-11m in ABC rotation: 3.0∠0°,
3.0∠–120°, 3.0∠120° amps to terminals D1 through D6 and 3.0∠180°, 3.0∠60°, 3.0∠–60° amps
to terminals F1 through F6.
Step 4: Slowly increase the A-phase current in CT circuit 1 or 2 until OUT2 closes. Record the time
between OUT2 and OUT1 closing. This should be 100 ms ± (50 ms + 2 cycles).
Step 5: (Optional) Repeat steps 1 through4 for settings group 1, 2, and 3.
Functional Test Reports
Restrained Pickup Verification (Maximum Restraint)
Pickup Accuracy = ±2% or ±0.05A, whichever is greater.
Dropout = (1 - 0.1) * pickup
Step
Low
High Low
High Pass/Fail