Sam Spade wrote:
IF you are going to make up a 100 ft, 10 gauge extension cord, then also get a 30 A to 50A adapter. That should plug into a "normal" dryer house circuit and use one 50 amp side.....which would be plenty to feed your 30 amp service.
A standard electric dryer outlet is not a 50A outlet, but a 30A outlet. If you're meaning a 30A RV to 50A RV adapter, it will not fit in a dryer outlet. It will work with a normal electric range outlet (of recent vintage), but that's usually not so convenient to use when visiting someone.
Be aware that many existing houses have three wire dryer outlets that do not have a safety ground connection (forcing the neutral return to do double-duty as a chassis ground), while new installations now have four wire dryer outlets with separate neutral and ground connections. If you construct or buy an adapter for a dryer outlet, you need to know which style you'll be dealing with, and be sure to wire it properly for RV usage. You should use only one of the two line connections and not the other in either case so as to provide 120V to the RV rather than 240V. Doing it incorrectly will lead to much damage to the RV 120V devices.