2019 Q23 — SEC Actuation With RP4 Loss

✓ D. Correct. 1RP4 is the main panel in the control room that gives a visual status of all safety related equipment including the Safeguard Equipment Controllers (SECs). Since 1RP4 is not safety related, the interface between the SECs and 1RP4 is isolated. Consequently, when a Reactor Trip and Safety Injection occurs, the SECs will automatically actuate in Mode 1.

✗ A. Incorrect but plausible. If DC power had been lost to a control room Bezel (e.g. AFW Control Bezel), then the components controlled by that Bezel could not been operated using the Bezel (manual and automatic functions). The candidate could apply this same logic to 1RP4 and incorrectly conclude that with DC power lost to 1RP4, then all equipment associated with 1RP4 can not be operated.

✗ B. Incorrect but plausible. The distractor is partially correct and the SECs can operate in Modes 1 through 4. However, for the given plant conditions, the SECs will not operate in Mode 3.

✗ C. Incorrect but plausible. The distractor is partially correct and the SECs can operate in Modes 1 through 4. However, for the given plant conditions, the SECs will not operate in Mode 2.

Ref: Notification 20787762, NOS05SEC000-07 (SAFEGUARDS EQUIPMENT CONTROL SYSTEM) | LO: Identify and describe the Control Room controls, indications, and alarms associated with the Safeguards Equipment Control System | Source: New | Cognitive: Higher