Q62 — Grid Disturbance SMD Runback Controls
APE: 077 Generator Voltage and Electric Grid Disturbances-AA1.02 (3.8)
Given:
• Unit 2 is at 100% Reactor Power
• The crew is performing S2.OP-AB.GRID-0001 (Abnormal Grid) Attachment 2 (Solar Magnetic Disturbance)
• The crew is preparing to initiate a generator load reduction to less than 942 MW (~77.6% RTP) at 15% / MIN from the TURBINE E-H CONTROL & STATUS touch screen monitor
In accordance with S2.OP-AB.GRID-0001, which ONE of the following completes the statements below?
With the turbine controls in OPERATOR MODE - AUTO, the PO will select ___ to initiate the generator load reduction.
• Unit 2 is at 100% Reactor Power
• The crew is performing S2.OP-AB.GRID-0001 (Abnormal Grid) Attachment 2 (Solar Magnetic Disturbance)
• The crew is preparing to initiate a generator load reduction to less than 942 MW (~77.6% RTP) at 15% / MIN from the TURBINE E-H CONTROL & STATUS touch screen monitor
In accordance with S2.OP-AB.GRID-0001, which ONE of the following completes the statements below?
With the turbine controls in OPERATOR MODE - AUTO, the PO will select ___ to initiate the generator load reduction.
A. SMD#1 RUNBACK ONLY
B. SMD#2 RUNBACK ONLY
C. SMD#1 RUNBACK then GO
D. SMD#2 RUNBACK then GO
▶ Show Answer & Explanation
✓ C. Correct. IAW S2.OP-AB.GRID-0001 (Abnormal Grid) Attachment 2 (Solar Magnetic Disturbance), the PO will depress SMD#1 RUNBACK and GO to initiate the generator load reduction.
✗ A. Incorrect but plausible. The TURBINE E-H CONTROL & STATUS touch screen monitor allows for manual entry of the setter and the reduction ramp rate. During manual entry the turbine won't move until the go button is depressed. Since the SMD#1 RUNBACK is a preset setter position with a preset ramp rate, the candidate could incorrectly conclude that only the SMD#1 RUNBACK button is depressed to start the load reduction.
✗ B. Incorrect but plausible. The TURBINE E-H CONTROL & STATUS touch screen monitor allows for manual entry of the setter and the reduction ramp rate. During manual entry the turbine won't move until the go button is depressed. Additionally, since there is a SMD#2 RUNBACK with a preset setter position with a preset ramp rate, the candidate could incorrectly conclude that only the SMD#2 RUNBACK button is depressed to start the load reduction.
✗ D. Incorrect but plausible. The candidate could incorrectly conclude that using the SMD#2 RUNBACK is required per S2.OP-AB.GRID-0001 Attachment 2. Pressing GO is required to start the turbine load reduction.
Ref: S2.OP-AB.GRID-0001 (Abnormal Grid) Attachment 2 | LO: NOS05ABGRID-12 — Describe, in general terms, the actions taken in S2.OP-AB.GRID-0001 (Q) and the bases for the actions in accordance with the Technical Bases Document | Source: New | Cognitive: Higher
Connections
- Related systems: 500KV, Main Turbine
- Related procedures: AB.GRID-0001 — Grid Disturbance
- Related exam: 2018 NRC Written Exam