Q64 — SGFP Trip / Turbine Runback / DEHC / 2CN47
T3 G2.1.19 (3.9)
Given:
- Salem Unit 2 is at 100% power
- All systems are in normal alignment and in Auto
Then:
- 21 SGFP trips
Which of the following indications is the expected response?
1. The DEHC will automatically runback the turbine at (1) per minute.
2. 2CN47, 23/24/25 Heater String Bypass valve, (2) immediately open when the feedpump trips.
- Salem Unit 2 is at 100% power
- All systems are in normal alignment and in Auto
Then:
- 21 SGFP trips
Which of the following indications is the expected response?
1. The DEHC will automatically runback the turbine at (1) per minute.
2. 2CN47, 23/24/25 Heater String Bypass valve, (2) immediately open when the feedpump trips.
A. (1) 15% (2) will NOT
B. (1) 15% (2) will
C. (1) 200% (2) will
D. (1) 200% (2) will NOT
▶ Show Answer & Explanation
✓ C. Correct. A SGFP will automatically initiate a turbine runback at 200% per minute to 66% power. When a SGFP trips the 2CN47 will open and the polisher will be bypassed.
✗ A. Plausible because this is the ramp rate when manually initiating a turbine runback at the DEHC panel. Plausible because on a condensate pump trip, the 2CN47 will only open if SGFP suction pressure lowers to less than 320 psig. Incorrect in that the 2CN47 will open following a SGFP trip regardless of suction pressure.
✗ B. Plausible because this is the ramp rate when manually initiating a turbine runback at the DEHC panel.
✗ D. Plausible because on a condensate pump trip, the 2CN47 will only open if SGFP suction pressure lowers to less than 320 psig. Incorrect in that the 2CN47 will open following a SGFP trip regardless of suction pressure.
Ref: S2.OP-AB.CN-0001 (R32) | LO: NOS05ABCN01-07, Objective 1.d. Describe the operation of the following system as applied to AB.CN-0001: SGFP Trip | Source: Bank - Salem | Cognitive: Fundamental/Memory
Connections
- Related systems: Feed & Condensate, Main Turbine
- Related procedures: AB.CN-0001 — Condensate System Abnormality
- Related exam: 2023 NRC Written Exam