Q80 — ATWS EOP-FRSM-1 Turbine Trip Verification
T1G1 EPE 29 EA2.09 (4.1)
Given:
- Salem Unit 2 reactor failed to automatically trip following a valid RPS trip signal
- All attempts to trip the reactor from the main control room have been unsuccessful
- The crew enters 2-EOP-FRSM-1, Response to Nuclear Power Generation, and all immediate actions are complete
In accordance with 2-EOP-FRSM-1, which of the following completes both statements?
1. Which of the following describes how the turbine trip status is checked?
2. What subsequent action will the CRS direct if the turbine trip status check is NOT met following immediate actions of 2-EOP-FRSM-1?
- Salem Unit 2 reactor failed to automatically trip following a valid RPS trip signal
- All attempts to trip the reactor from the main control room have been unsuccessful
- The crew enters 2-EOP-FRSM-1, Response to Nuclear Power Generation, and all immediate actions are complete
In accordance with 2-EOP-FRSM-1, which of the following completes both statements?
1. Which of the following describes how the turbine trip status is checked?
2. What subsequent action will the CRS direct if the turbine trip status check is NOT met following immediate actions of 2-EOP-FRSM-1?
A. (1) ALL turbine stop valve closed bi-stables LIT on 2RP4. (2) Dispatch an operator to locally trip the turbine at the front standard.
B. (1) ALL turbine stop valve closed bi-stables LIT on 2RP4. (2) Direct the control room operator to stop all EHC pumps.
C. (1) 2 out 3 Auto Stop Oil low pressure bi-stables LIT on 2RP4. (2) Direct the control room operator to stop all EHC pumps.
D. (1) 2 out 3 Auto Stop Oil low pressure bi-stables LIT on 2RP4. (2) Dispatch an operator to locally trip the turbine at the front standard.
▶ Show Answer & Explanation
✓ A. Correct. Per 2-EOP-FRSM-1 Step 6, the turbine is tripped when all stop valves are closed. This can be verified by observing the bi-stables on 2RP4. If the turbine fails to trip at Step 6, then the CRS will dispatch an operator to the turbine deck to locally trip the turbine at the front standard.
✗ B. First part is correct. Second part is incorrect. Plausible because stopping EHC pumps is possible from the control room. Incorrect in that FRSM-1 step 6 directs locally tripping the turbine at the front standard.
✗ C. First part is incorrect. Plausible because 2 out of 3 ASO bi-stables tripped is a demand for a turbine trip. Incorrect in that ASO indications is not a direct indication of a turbine trip. Second part is incorrect. Plausible because stopping EHC pumps is possible from the control room. Incorrect in that FRSM-1 step 6 directs locally tripping the turbine at the front standard.
✗ D. First part is incorrect. Plausible because 2 out of 3 ASO bi-stables tripped is a demand for a turbine trip. Incorrect in that ASO indications is not a direct indication of a turbine trip. Second part is correct.
Ref: 2-EOP-FRSM-1 (R43) | LO: NOS05FRSM00-05, Objective 4.iii | Source: New | Cognitive: Comprehension/Analysis
Connections
- Related systems: Main Turbine, Rx Vessel & Internals
- Related EOPs: EOP-FRSM-1 — Response to Nuclear Power Generation
- Related exam: 2023 NRC Written Exam