Q81 — Grid Voltage Inoperable Lines
000077G2.1.7 (4.7)
Given:
• Unit 2 is at 100% Power.
• The voltages on the following 500 KV Lines are as follows:
Based on the above conditions, complete the following statements:
(1) The CRS will declare the __(1)__ 500 KV line(s) INOPERABLE.
(2) The CRS will direct performing __(2)__ of S2.OP-AB.GRID-0001, Abnormal Grid Disturbances.
Note: ESO = Electric System Operator
• Unit 2 is at 100% Power.
• The voltages on the following 500 KV Lines are as follows:
| Orchard (5021) | New Freedom (5024) | Salem-Hope Creek Tie (5037) |
| 492 KV | 495 KV | 497 KV |
(1) The CRS will declare the __(1)__ 500 KV line(s) INOPERABLE.
(2) The CRS will direct performing __(2)__ of S2.OP-AB.GRID-0001, Abnormal Grid Disturbances.
Note: ESO = Electric System Operator
A. (1) 5021
(2) Station Load Curtailment in accordance with Attachment 3, Salem 500 KV Switchyard Low Voltage,
(2) Station Load Curtailment in accordance with Attachment 3, Salem 500 KV Switchyard Low Voltage,
B. (1) 5021 and 5024
(2) Station Load Curtailment in accordance with Attachment 3, Salem 500 KV Switchyard Low Voltage,
(2) Station Load Curtailment in accordance with Attachment 3, Salem 500 KV Switchyard Low Voltage,
C. (1) 5021 and 5024
(2) Generator Load Reduction as specified by the ESO in accordance with Attachment 4, 500 KV Grid Instability,
(2) Generator Load Reduction as specified by the ESO in accordance with Attachment 4, 500 KV Grid Instability,
D. (1) 5021
(2) Generator Load Reduction as specified by the ESO in accordance with Attachment 4, 500 KV Grid Instability,
(2) Generator Load Reduction as specified by the ESO in accordance with Attachment 4, 500 KV Grid Instability,
▶ Show Answer & Explanation
✓ A. Correct. S2.OP-AB.GRID-0001(Q), Attachment 3 states if 500 KV Switchyard Voltage is < 493 KV, then declare the associated off-site power source inoperable and then initiate Station Load Curtailment IAW OP-AA-108-107-1001, Electric System Emergency Operations and Electric System Operator Interface.
✗ B. Incorrect. The first part is plausible because the candidate may confuse the voltage threshold for declaring an off-site power source inoperable. The second part is correct.
✗ C. Incorrect. The first part is plausible because the candidate may confuse the voltage threshold for declaring an off-site power source inoperable. The second part is plausible because Attachment 4 of AB.GRID requires a power reduction at 15%/min max for 500 KV Grid instabilities.
✗ D. Incorrect. The first part is correct. The second part is plausible because Attachment 4 of AB.GRID requires a power reduction at 15%/min max for 500 KV Grid instabilities.
Ref: S2.OP-AB.GRID-0001(Q), Abnormal Grid and bases | LO: N/A | Source: Modified, Salem 2019 NRC Exam, Q62 | Cognitive: Fundamental
Connections
- Related systems: 500KV
- Related procedures: AB.GRID-0001 — Grid Disturbance, OP-AA-108-107-1001 — Electric System Emergency Operations
- Related exam: 2020 NRC Written Exam