RV Repair: Battery or electrical problem, deep cycle battery, chassic

Question
We were connected to electricity at the campground, shouldn't the lights also run off electricity. It is a motorhome, I apoligize for not stating that in my earlier email.


Followup To
Question -
We purchased a 1977 Windjammer and did not have a problem starting it or the generator. We had new brakes, shocks, and tires put on it.
We decided to go camping for the weekend and that is when the problems started.
The first night at the camp park, everything was working fine off electricity, except the lights were kind of dim. About 5:00 a.m. the lights went out but all the rest of the electrical things worked. That morning our battery was dead. We got a jump and the lights started working again, but we turned them off just in case the lights were draining the battery.
We tried to start the RV again about an hour later and the battery was dead again.
We waited until the next day and got another jump and drove home, which took about an hour.
When we tried to start it again an hour later the battery was dead again.
Answer -
I am not familiar with a Windjammer but will assume it's a motor home.  If it's like most others, it has two batteries, one for the coach and one for the chassic.  Have them both tested and replace both if needed making sure the coach battery is a deep cycle battery.

Answer
I don't think you were running off shore power this weekend, I think you were trying to run off your battery.  Most RV's have a converter that does a couple of things, one being to charge your battery.  It's obvious your's is not working or your lights should have been very bright (usually the sign it's working). The converter switches you between shore and battery as the plug is pulled or connected.