Generator Hookup Sizing
Add up running watts, then add the single largest starting surge (motors start one at a time). Edit any wattage to match nameplates.
OnLoadQtyRun WStart W
Inlet, cord & breaker
| Generator outlet | Max power @240 V | Inlet | Cord | Backfed breaker |
|---|---|---|---|---|
| L14-30R | 7,200 W | 30 A L14-30P inlet | 10 AWG 4-wire SOOW/STW | 30 A 2-pole |
| 14-50R / CS6364 | 12,000 W | 50 A CS6365 / SS2-50 inlet | 6 AWG (8 AWG listed cords common — check) | 50 A 2-pole |
Interlock vs transfer switch. A listed interlock kit (made for that panel brand/model) mechanically prevents the main and generator breakers from being on together; the whole panel is available and you load-manage by hand. A manual transfer switch moves pre-selected circuits only. A standby generator needs an ATS — service-rated if ahead of the main — and the generator must be sized for the transferred load per 702.4(B) (or use load management). Backfed breakers need a hold-down (408.36(D)). Generator conductors to the first OCPD: ≥115% of nameplate current (445.13). Check the bonded/floating neutral: with a 3-pole-neutral-not-switched setup, portable generators used with an interlock typically need a floating neutral. Most jurisdictions require a permit for interlock/inlet and standby generator installs.
Morningstar Electric LLC is a dealer for DuroMax portable/dual-fuel generators and EG4 inverters and batteries. Always size to the specific model's continuous (rated) output, not peak, and follow its manual.
Reference only — not engineering, legal, or code-compliance advice. Results are estimates for qualified persons and must be verified against the NEC edition adopted where the work is done (your selected edition), manufacturer instructions, and the local AHJ. Use is subject to the Terms of Use & Disclaimer. — Morningstar Electric LLC