AB.ROD-0001 — Immovable/Misaligned Control Rods
Purpose
Provides guidance for responding to immovable or misaligned control rods, including rod deviation alarms, diagnosis, load reduction requirements, and recovery procedures.
Key Actions / Information
Exam — 2022 Q20
Misaligned rod recovery procedure: Lift Coil Disconnect Switches for all rods in the affected bank are placed in OFF (disconnected), EXCEPT for the misaligned rod which remains ON (connected). The Rod Bank Selector Switch is placed to the position matching the affected bank — for a control rod in D bank, use CBD (Control Bank D), not SBD (Shutdown Bank D).
Exam — 2020 Q20
AB.ROD-0001 directs placing the unit in Hot Standby if more than one rod is stuck/misaligned. If only ONE rod is misaligned, the action is to reduce power to < 75% RTP (per TS 3.1.3.1 action c.3.d) — do not confuse with the > 1 rod action. Also note: AB.ROD-0001 directs reviewing QPTR. If QPTR TS limits exceeded, TS 3.2.4 requires reducing power to < 50% if QPTR is not returned to within limits after 24 hours — this is a separate QPTR-based action, not the rod misalignment action.
Connections
- Related systems: RPS/SSPS, Control Rod Drive, Stator Cooling Water
- Related procedures: AB.ROD-0003 — Continuous Rod Motion
- Related tech specs: TS 3/4.1.3 — Movable Control Assemblies, TS 3/4.2 — Power Distribution
- Related exam questions: 2020 Q20, 2022 Q20
- Related exam: 2020 NRC Written Exam, 2022 NRC Written Exam