Q8 — CCW / RCP Motor Bearing Temp
APE 26 AA2.04 (2.5)
Given:
• Unit 2 is at 100% Power.
• The RO reports the following:
- CCW Surge Tank Levels are lowering slowly.
- 2DR107, Surge Tank Make-up Valve, is opened and Surge Tank level is stable at 42 %.
- OHA A-41, AUX ALM SYS PRINTER, annunciates for Containment Sump Pump start then stops 5 seconds later.
- The RO reports 23 RCP motor bearing temperatures are 160 °F and rising at 0.5 °F per minute.
• The crew enters S2.OP-AB.CC-0001, Component Cooling Abnormality.
Based on current plant conditions and in accordance with S2.OP-AB.CC-0001, which ONE of the following is the MAXIMUM time allowed before tripping the reactor and stopping the RCP?
• Unit 2 is at 100% Power.
• The RO reports the following:
- CCW Surge Tank Levels are lowering slowly.
- 2DR107, Surge Tank Make-up Valve, is opened and Surge Tank level is stable at 42 %.
- OHA A-41, AUX ALM SYS PRINTER, annunciates for Containment Sump Pump start then stops 5 seconds later.
- The RO reports 23 RCP motor bearing temperatures are 160 °F and rising at 0.5 °F per minute.
• The crew enters S2.OP-AB.CC-0001, Component Cooling Abnormality.
Based on current plant conditions and in accordance with S2.OP-AB.CC-0001, which ONE of the following is the MAXIMUM time allowed before tripping the reactor and stopping the RCP?
A. 15 minutes
B. 20 minutes
C. 25 minutes
D. 35 minutes
▶ Show Answer & Explanation
✓ C. Correct. IAW S2.OP-AB.CC-0001 Attachment 1, reactor trip and stopping affected RCP is required when motor bearing temperature reaches 175 °F. At 25 minutes RCP bearing temperature will be 172.5 °F which is still below the 175 °F limit. Note: S2.OP-AB.RCP-0001 Attachment 1 uses motor bearing temperature greater than 175 °F.
✗ A. At 15 minutes the temperature will be 167.5 °F which is still below the 175 °F limit.
✗ B. At 20 minutes the temperature will be 170 °F which is still below the 175 °F limit.
✗ D. At 35 minutes the temperature will be 177.5 °F which has exceeded the 175 °F limit.
Ref: S2.OP-AB.CC-0001 Rev 19 | LO: NOS05ABCC01, Objective 4 | Source: New | Cognitive: Comprehension/Analysis
Connections
- Related systems: CCW, RCPs
- Related procedures: AB.CC-0001 — Loss of Component Cooling Water
- Related exam: 2022 NRC Written Exam