Q64 — Main Turbine Valve Stroke Testing
045 G2.1.23 (4.3)
Given:
• Unit 2 is at 89% Power.
• Main Turbine Valve testing is in progress in accordance with S2.OP-PT.TRB-0003, Main Turbine Valve Stroke Testing.
In accordance with S2.OP-PT.TRB-0003, which ONE of the following completes the statement?
While performing the valve stroke test, if a _(1)_ valve does NOT reopen, then the operator is required to _(2)_.
• Unit 2 is at 89% Power.
• Main Turbine Valve testing is in progress in accordance with S2.OP-PT.TRB-0003, Main Turbine Valve Stroke Testing.
In accordance with S2.OP-PT.TRB-0003, which ONE of the following completes the statement?
While performing the valve stroke test, if a _(1)_ valve does NOT reopen, then the operator is required to _(2)_.
A. 1) Reheat or Intercept
2) reduce turbine load to < 75% within an hour
2) reduce turbine load to < 75% within an hour
B. 1) Reheat or Intercept
2) trip the reactor
2) trip the reactor
C. 1) Governor or Stop
2) reduce turbine load to < 75% within an hour
2) reduce turbine load to < 75% within an hour
D. 1) Governor or Stop
2) trip the reactor
2) trip the reactor
▶ Show Answer & Explanation
✓ C. Correct. IAW S2.OP-PT.TRB-0003, P&L step 3.12.3, except for short periods during testing, if any HP turbine inlet valve (MS28/MS29) closes and does not reopen or must be isolated by the operator, then turbine load should be reduced to 75% within one hour.
✗ A. Incorrect. Plausible if the operator believes that the requirement to reduce power to 75% within one hour is for a Reheat or Intercept valve. First part is incorrect. IAW S2.OP-PT.TRB-0003 P&L step 3.12.6, except for short periods during testing, the Main Turbine should NOT be operated above 80% load with a Reheat Stop Valve or Intercept Valve closed. Do Not exceed 5 minutes with any valve closed before beginning to reduce load at 10%/hr. Continue load reduction until either the valve is open or less than 80% load is achieved. Second part is correct.
✗ B. Incorrect. Plausible if the operator believes that the requirement to reduce power to 75% within one hour is for a Reheat or Intercept valve. First part is incorrect. IAW S2.OP-PT.TRB-0003, P&L step 3.12.3, except for short periods during testing, if any HP turbine inlet valve (MS28/MS29) closes and does not reopen or must be isolated by the operator, then turbine load should be reduced to 75% within one hour. Second part is incorrect. Reactor trip is not required by procedure.
✗ D. Incorrect. Plausible if the operator believes that a reactor trip is required when a Governor or Stop valve is closed. See answer C for further explanation.
Ref: S2.OP-SO.TRB-0001 (R49) | LO: NOS05GEN002-07, Obj 12 — Identify and describe the Control Room controls, indications, and alarms associated with the Unit 2 Main Generator and Hydrogen Cooling System | Source: New | Cognitive: Fundamental/Memory
Connections
- Related systems: Main Turbine
- Related procedures: S2.OP-PT.TRB-0003 — Main Turbine Valve Stroke Testing
- Related exam: 2022 NRC Written Exam