Can't run A/C at home: solved -- see 8/21/16 update

profdant139 wrote:
It's hot in Calif, and I want to use the trailer as a lifeboat -- but the a/c won't run off garage power. Here is the setup and the problem -- I attach our 30 amp cord to a heavy construction grade extension cord (not a little thin cord), using an adapter. The two cords total about 40 feet in length. The extension cord plugs into a wall socket in the garage.

The a/c starts ok, and runs for a minute or so, quits, starts again, and quits.

Is this because of the length of the cords? Would an even heavier extension cord help? Is this due to some limitation on our wall socket? I run woodworking equipment on the same socket, with no problems. And the circuit breaker does not trip.

Thanks in advance for your advice. (Yes, I know I should know much more about electrical power than I do, but I don't. So please forgive my pathetic ignorance.)

I read through most of this and people have suggested testing the voltages. It really is easy and i have some pictures for you to see how easy it is. The multimeter i got from sears for maybe 20-25 bucks and it's a very good investment, especially if you ask questions on here since people like Mex will want numbers for more accurate troubleshooting.

First link: Picture

This shows how to set the multimeter. Just make sure it is on Vac and -200- like in the picture.

Second link: Picture

This picture shows me testing an extension cord and the idea applies to outlets as well.

Third link: Picture

This one shows the tester leads switched around.
Hope these help you out.

Edit: Sorry for the sideways picture, i was too lazy to rotate them.