keeping batteries charged

fgmill wrote:
I purchased a 31ft travel Trailer which I plan to store in back yard for now while not in use. I do not have hook up available right now and want to run the basics (lights,radio,heater occasionally) off batteries. Can I leave a trickle charger plugged in with out damaging converter?

A trickle charger or battery minder requires the battery to be fully charged before hand. It will do nothing to keep the battery charged if loads exceed the trickle chargers output. As others have said just plug in your shore power, check battery levels about once a month. If your converter is a WFCO, junk it and get a Progressive Dynamics with pendant or Iota with IQ4.