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Generator interlock checklist playbook

Goal​

Install a safe, listed generator interlock or transfer setup that prevents backfeed.

Inputs you must know before you start​

  • Generator type (portable or fixed) and output rating.
  • Panel model and available interlock kits.
  • AHJ requirements for transfer equipment and signage.

The path (in order)​

  1. Select listed transfer equipment or interlock kit for the panel.
  2. Provide a proper inlet and generator disconnecting means.
  3. Verify mechanical interlock prevents parallel sources.
  4. Label the panel, inlet, and operating steps clearly.
  5. Test operation with utility and generator power.

This is​

A checklist to keep optional standby installations safe and code-compliant.

This is not​

A generator sizing or load management guide.

Inspection-ready checklist​

  • Interlock or transfer device is listed for the panel.
  • Generator disconnecting means provided as required.
  • Backfeed is mechanically prevented.
  • Clear labels and operating instructions are installed.
  • Source switching is tested and documented.

Worked example​

A portable generator feeds a listed inlet and a panel interlock kit made for that panel. The main and backfeed breaker are mechanically interlocked, and the panel is labeled with step-by-step operating instructions.

Cross references​

  • Primary: 702.4, 702.6, 445.18
  • Secondary: 110.3(B), 230.82

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