Debate: Is it ever okay to backfeed a panel with a generator cord?

I was on a service call in Fresno last month where the power was out for 6 hours. Homeowner had a portable generator and wanted me to show him how to backfeed through a dryer outlet. I told him no way, that's how you kill linemen. But then another sparky on site said as long as you flip the main breaker its fine. What do you guys think, is there any safe scenario for backfeeding or is it always a no-go?

3 comments

3 Comments

elizabeth_bailey262mo ago

I read somewhere that even with the main off, those backfeed setups can still cause arcing when you plug in the cord, especially if the generator is already running. Plus the risk is real if someone forgets to flip the main back or the breaker fails. Had an old timer tell me a story about a guy in Bakersfield who thought he knew what he was doing, ended up frying his generator and almost starting a fire.

hernandez.brooke2mo ago

That story about the guy in Bakersfield is exactly why I always tell people to shut the generator off before plugging or unplugging anything. I've seen the inside of a melted inlet port before, and it's not worth saving two minutes of your time. If you're doing the backfeed thing, at least use a real interlock kit and a proper power inlet box so you're not relying on memory alone.

park.riley2mo ago

Arcing is definitely a thing, but if you do it right with a proper interlock and inlet, it's pretty much the same as plugging into any other outlet in your house... I've seen way more problems from people just running extension cords through windows and doors than from a properly installed backfeed setup.