Appendix D: Acceptance Test Procedures
ISGS Acceptance Test | Directional Phase Time Overcurrent (67) Function |
(continued)
Phase
A B C
(Phase-Neutral Connected VTs)
Pickup LED illuminates.
Wisdom software records pickup in event log.
Return current to zero and reset timer.
Timing
5.Apply appropriate value of current in reverse direction for the test. The results match Table D.5. Pickup LED illuminates.
Display shows PICKUP 67 P12 (23, 31). Wisdom software records pickup in event log.
6.Relay times out per Table D.5. Trip LED illuminates.
Timer stops as Trip 1 contacts close.
Trip log indicates trip current value and time in pickup. Wisdom software records trip on directional overcurrent. Return current to zero and reset timer.
7.Remove control power from relay for five seconds, then restore it. Trip LED
8.Reset relay target. Trip LED resets.
D
Repeat above steps for phase
Testing may also be done for each phase at the user settings following the same procedure.
Table D.5 Test Points for Very Inverse Curve Characteristics
Multiple of Pickup | Time Band 2 (seconds) | Time Band 5 (seconds) | Time Band 9.9 | (seconds) |
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2X | 3.73 | 9.30 | 18.38 |
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4X | 0.92 | 2.27 | 4.46 |
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8X | 0.40 | 0.96 | 1.87 |
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Accuracy of the time curve for 2 ≤ I/Ip ≤ 20 is 5% from the defined value, or 30 ms, whichever is greater.
Siemens Energy & Automation, Inc. | 73 |
