Q57 — In-Core Temperature Monitoring / CET Reference Junction
T2G2 017 K6.01 (3.2)
Given:
- Salem Unit 2 is at 100% power
Then:
- The ventilation system that supplies cool air to the room that the Reference Junction Panel is located for the In-Core Temperature Monitoring System is lost
- Room temperature have risen by 15 degrees F
Which of the following describes the impact on the In-Core Monitoring instrumentation and what is its design limit?
- Salem Unit 2 is at 100% power
Then:
- The ventilation system that supplies cool air to the room that the Reference Junction Panel is located for the In-Core Temperature Monitoring System is lost
- Room temperature have risen by 15 degrees F
Which of the following describes the impact on the In-Core Monitoring instrumentation and what is its design limit?
A. CET readings will indicate higher than actual; up to 3300 degrees F.
B. CET readings will indicate higher than actual; up to 2300 degrees F.
C. NO effect on CET readings as they are temperature compensated; up to 2300 degrees F.
D. NO effect on CET readings as they are temperature compensated; up to 3300 degrees F.
▶ Show Answer & Explanation
✓ C. Correct. The reference junction box is located outside of containment. Ambient temperature changes in the room will affect the reference junction box, however the system uses a temperature compensator to adjust for the changes in temperatures where the reference junction box is located. A rise in ambient room temperature will raise temperature, but the temperature compensating circuit will adjust for these reference junction box temperature changes. In-Core system design upper range is 2300 degrees F.
✗ A. Plausible because higher temperatures in the room where the reference junction box is located will cause the in temperature indicated to rise. Incorrect in that the system has a temperature compensator circuit such that the reference junction box temperature changes are adjusted to the true thermocouple reading. In-core system has a design range to 2300 degrees F.
✗ B. Plausible because higher temperatures in the room where the reference junction box is located will cause the in temperature indicated to rise. Incorrect in that the system has a temperature compensator circuit such that the reference junction box temperature changes are adjusted to the true thermocouple reading. In-core system has a design range to 2300 degrees F.
✗ D. In-Core system design upper range is 2300 degrees F.
Ref: INPO Sensors and Detectors (R3) | LO: NOS0SINCORE-09, Objective 7 — Describe how the following components affect the Core Exit Thermocouple System during Normal and Abnormal conditions: Reference Junction Boxes | Source: Bank — Indian Point 2 2021 NRC ROSS | Cognitive: Comprehension/Analysis
Connections
- Related systems: RPS/SSPS
- Related exam: 2023 NRC Written Exam