5 • testing, Introduction, Operational tests – Basler Electric BE1-47N User Manual
Page 37: Negative sequence voltage pickup and dropout
9170400990 Rev J
BE1-47N Testing
5-1
SECTION 5 • TESTING
Introduction
The following procedures verify proper relay operation and calibration.
Results obtained from these procedures may not fall within specified tolerances. When evaluating results,
consider three prominent factors:
•
Test equipment accuracy
•
Testing method
•
External test set components tolerance level
Operational Tests
Operational tests include pickup and dropout of negative sequence voltage protection, overvoltage
protection, and undervoltage protection.
Negative Sequence Voltage Pickup and Dropout
BE1-47N accuracy verification requires a simultaneous test of the three phases. Such a comprehensive
test involves careful monitoring of all phase voltages and phase angles, and the calculation of the
negative sequence voltage values. However, it is possible to obtain confirmation of the essential integrity
of the relay without resorting to methods that are more suited to a laboratory.
Accordingly, the following single-phase verification test is offered as an adequate accuracy and calibration
test that is easy to set up and perform.
1. Adjust the Negative Sequence Pickup switch to the K (20%) position.
2. As shown in Figure 5-1, short-circuit or jumper case terminals 7 (B-phase) and 8 (C-phase).
3. Using Table 5-1 as a guide, apply voltage, at nominal frequency, to case terminal 6 (A-phase) and 7
(phases B and C). The Negative Sequence Pickup LED should light.
Table 5-1. Negative-Sequence Test Voltage
Sensing Input Range
Voltage Input
3) 120 Vac, 60 Hz
41.57 Vac +2.08 Vac, 60 Hz
4) 100 Vac, 50 Hz
34.64 Vac +1.73 Vac, 50 Hz
5) 208 Vac, 60 Hz
72.05 Vac +3.60 Vac, 60 Hz
6) 173 Vac, 50 Hz
59.93 Vac +3.00 Vac, 50 Hz
4. Vary the input to verify the setting.
5. Lower the input voltage until the pickup LED turns off. Record the input voltage. Dropout should be
within 2% of the pickup value (i.e., input voltage at time of pickup, LED on).
Further pickup settings may be verified at this time. The following formulas determine the input
voltages, based on sensing range, which will cause the pickup LED to light.
120
3
1
2
2
∠
∝=
∝
+
∝
+
=
where
V
V
V
V
C
B
A
Equation 5-1
For line-to-line voltage:
∝
+
∝
+
=
CA
BC
AB
V
V
V
V
LL
2
2
3
1
Equation 5-2