Q56 — Rod Insertion Limit Alarm
001 K5.04 (4.3)
Given:
• Unit 2 is at 85% Power following a rapid load reduction.
• OHA E-8, ROD INSERT LMT LO, is now LIT.
• Tavg is 571°F and stable.
• Tref is 570°F and stable.
Which ONE of the following completes both statements?
1. The Control Rod Insertion Limit of the Core Operating Limits Report (COLR) _(1)_ been exceeded.
2. Per the OHA Alarm Response Procedure for E-8, the NEXT action that the operating crew is required to perform is _(2)_.
• Unit 2 is at 85% Power following a rapid load reduction.
• OHA E-8, ROD INSERT LMT LO, is now LIT.
• Tavg is 571°F and stable.
• Tref is 570°F and stable.
Which ONE of the following completes both statements?
1. The Control Rod Insertion Limit of the Core Operating Limits Report (COLR) _(1)_ been exceeded.
2. Per the OHA Alarm Response Procedure for E-8, the NEXT action that the operating crew is required to perform is _(2)_.
A. 1) has NOT
2) initiate an emergency boration IAW S2.OP-SO.CVC-0008, Rapid Borate
2) initiate an emergency boration IAW S2.OP-SO.CVC-0008, Rapid Borate
B. 1) has NOT
2) initiate a normal boration IAW S2.OP-SO.CVC-0006, Boron Concentration Control
2) initiate a normal boration IAW S2.OP-SO.CVC-0006, Boron Concentration Control
C. 1) has
2) initiate a normal boration IAW S2.OP-SO.CVC-0006, Boron Concentration Control
2) initiate a normal boration IAW S2.OP-SO.CVC-0006, Boron Concentration Control
D. 1) has
2) initiate an emergency boration IAW S2.OP-SO.CVC-0008, Rapid Borate
2) initiate an emergency boration IAW S2.OP-SO.CVC-0008, Rapid Borate
▶ Show Answer & Explanation
✓ B. Correct. OHA E-8 alarms when the rods are 10 steps from the Rod Insertion Limit. Therefore, the RIL for the COLR has not been exceeded. IAW the OHA alarm response procedure, the crew is required to initiate a normal boration IAW S2.OP-SO.CVC-0006 to restore rods to their normal band.
✗ A. Part 1 is correct. Part 2 is incorrect. Plausible because emergency boration was required when OHA E-16, ROD INSERT LO-LO, was in alarm. This requirement has been removed from the OHA alarm procedures.
✗ C. Part 1 is incorrect. The OHA E-8 alarm indicates the rods are within 10 steps of the RIL. Part 2 is correct.
✗ D. Part 1 is incorrect. The OHA E-8 alarm indicates the rods are within 10 steps of the RIL. Part 2 is incorrect. Plausible because emergency boration was required when OHA E-16, ROD INSERT LO-LO, was in alarm. This requirement has been removed from the OHA alarm procedures.
Ref: S2.OP-AR.ZZ-0005 (R26) | LO: NOS05RODS00-14, Obj 6 — Describe the function of the Rod Insertion Limit Comparator | Source: Bank — Beaver Valley 2018 NRC RO61 | Cognitive: Comprehension/Analysis
Connections
- Related systems: Control Rod Drive, CVCS
- Related procedures: S2.OP-AR.ZZ-0005 — Overhead Annunciators Window E
- Related exam: 2022 NRC Written Exam