Generator Outage Planning Checklist: 15 Things to Do Before Your Window Opens

Generator outage planning is one of the highest-leverage activities in power plant maintenance. The decisions made in the weeks before the outage window opens determine whether the outage runs on schedule, on budget, and returns the machine to service in the condition the plant needs.

This checklist covers 15 items that should be completed before your outage window opens. It is structured around four phases: scope validation, technical review, resource confirmation, and return-to-service readiness.

Phase 1: Scope Validation (Items 1–4)

1. Review machine history and trending data. Confirm that the proposed scope addresses known issues and trending parameters. Scope that ignores operating data is scope that will be revised mid-outage.
2. Validate scope against OEM inspection intervals. Confirm that the proposed scope meets or exceeds OEM-recommended intervals for the machine's age and operating hours.
3. Identify deferred items from the previous outage. Every deferred item from the last outage should be on the scope unless there is a documented technical basis for continued deferral.
4. Confirm that scope aligns with insurance and regulatory requirements. For nuclear and regulated utility assets, confirm that the outage scope satisfies all applicable maintenance rule, NERC, and insurance requirements.

Phase 2: Technical Review (Items 5–9)

5. Review excitation system condition and history. Confirm that excitation system inspection is included if the machine is approaching major inspection intervals or has had any protection events since the last outage.
6. Confirm EL CID testing is included for major inspections. EL CID testing should be standard on any major inspection. If it is not in scope, document the technical basis for exclusion.
7. Review partial discharge history and trending. If online PD monitoring data is available, review it before finalizing scope. Elevated PD activity may indicate scope additions are warranted.
8. Confirm rotor inspection scope is appropriate. For machines with rotor winding history or elevated RSO test trends, confirm that rotor inspection scope is adequate.
9. Review acceptance criteria for all planned tests. Confirm that acceptance criteria are documented before the outage begins. Acceptance criteria should not be determined after test results are in hand.

Phase 3: Resource Confirmation (Items 10–12)

10. Confirm contractor qualifications and availability. Verify that all contractors have the required qualifications for the planned scope and are confirmed available for the outage window.
11. Confirm parts and materials availability. Long-lead parts should be on order or in inventory before the outage window opens. Mid-outage parts shortages are a primary driver of schedule overruns.
12. Confirm engineering oversight resources. Identify who will provide engineering oversight during the outage. For high-consequence scope, independent engineering oversight should be confirmed in advance.

Phase 4: Return-to-Service Readiness (Items 13–15)

13. Confirm return-to-service test plan. The return-to-service test plan should be documented before the outage begins, not assembled from whatever tests were completed.
14. Identify who will conduct the return-to-service review. Confirm whether the return-to-service review will be conducted internally, by the contractor, or by an independent engineering party.
15. Confirm system readiness for return to service. Confirm that all system interfaces (protection systems, excitation, controls, cooling) are ready to support return to service before the outage window closes.