WattStart here: your generator will probably throw a ground fault
Most portable generators ship with a floating neutral. Plug an EV charging cable into one and it faults out immediately — no charge, just a blinking light. It isn't broken. It needs a bonding plug, and almost nobody explains this before you're standing in the cold.
Guides
The bonding plug problem
Why your EV won't charge from a generator, and the $20 part that fixes it.
What size generator?
Derating, continuous load, and why the sticker wattage lies to you.
Inverter only — why
Conventional generators run 15–25% THD. What that does to an onboard charger.
Charge rate calculator
Enter your generator's rating, get a safe amperage and miles per hour.
The test rig
Photo goes here
The generator running with the 14-50 cable to the car — the shot that proves the whole site.
Drop it at
Drop it at
/assets/rig.jpg.Everything published here is measured on hardware I own and run, not spec sheets I read.
| Component | What it is |
|---|---|
| Generator | GENMAX GM10500XiT — open-frame tri-fuel inverter, 7,800W running on gasoline, under 3% THD |
| Bonding | Factory-supplied twist-lock bonding plug, installed and verified |
| Connection | NEMA 14-50R to Tesla Mobile Connector |
| Vehicle | Tesla Model Y |
| Climate | Northern Vermont — which means the cold-weather numbers are real |
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