AB.LOOP-0003 — Partial Loss of Offsite Power
Purpose
Provides operator actions for responding to a partial loss of offsite power, where one or more (but not all) offsite power sources are lost. Includes guidance for evaluating remaining sources, re-energizing lost buses, and cross-tie operations.
Key Actions / Information
Scenario — 2020 #1
Loss of #4 SPT de-energizes 500 KV Bus Section 1 and 23 CW Bus. All Vital Buses remain energized from 24 SPT (single offsite source). Attachment 4 provides steps to re-energize 23 CW Bus from Bus Section 24 via cross-tie breaker 2CW2BD. Verify Bus Section 24 voltage is within 4.22-4.36 KV before closing cross-tie. CRS enters TS 3.8.1.1 Action C for one offsite source and one EDG inoperable.
Connections
- Related systems: 500KV, 4KV, EDGs, Circ Water
- Related EOPs: EOP-TRIP-1 — Reactor Trip or Safety Injection, EOP-LOPA-1 — Loss of All AC Power
- Related procedures: AB.LOOP-0001 — Loss of All Offsite Power
- Related scenarios: 2020 Scenario 1 — Power Ascension / Station Blackout
- Related exam: 2020 NRC Operating Exam