You need to use one of these to test your house 15A receptacle before plugging into it.


Also always insure all three conductors are being used on the adapters. Some folks have cut the GROUND off of an extension cord or adapter.
I would never use a small round adapter but rather use a RV30A-15A long 'dogbone' type adapter (WALMART has them). The small round adapter always seem to get HOT for me and I was afraid of burning up my 30AMP shore power plug.

This is what I use to adapt to the 30-AMP RV plug from the 120VAC 15A receptacle or from the end of a 50-foot long HD Extension Cord (10-3) plugged into the house 15-AMP receptacle.

You don't want your 30AMP SHORE POWER PLUG to look like this from overheating the contacts.

Just my experience plugging into the house/garage 15-AMP receptacle.
Roy Ken