Is this a possibility?

lc0338 wrote:
Have a portable self contained 12 volt solar generator with 4ea 6 volt full river batteries. My RV currently has 2ea 12 volt house batteries and a separate 12 volt battery located near the on-board onan propane generator. My current set-up plan is to sit the solar generator in the sun and park my RV in the shade and run an 110 volt extension cord in-between (during heat of summer).

Would be good if you could post some specs on the solar generator unit. I don't know how familiar anyone here is with those. I've never seen one. Having said that, I doubt that it puts out enough power to run your A/C for more than a few minutes, even in full sun. Which I assume is your goal, since you mentioned summer heat. I'm just thinking that "portable self-contained" does not have much solar capacity. Need specs.

lc0338 wrote:
My question - If winter camping someplace and the solar generator could be sitting very close to the RV (within 10 feet say) would it be possible to connect the solar generator batteries to the 2ea house batteries (with jumper cables or heavy gauge wire / anderson connectors)?

I would still have an extension cord attached between the generator and RV and would of course have to turn on the inverter to generator 110 volt from the solar generator, when needed, but if I could connect the 2ea battery systems directly it would eliminate the need for the RV converter to have to cycle to charge the 2ea RV/house batteries. I don't want to damage either battery system. The solar generator has a battery monitor so I presume if the 2ea battery systems were hooked together as a second question would the battery monitor also be monitoring the 2ea RV batteries since there are all connected together?

12VDC can come from multiple sources, and as long as polarity matches up, nothing blows up. But what you describe would have the batteries trying to charge themselves, due to the onboard converter. If you turned that off, I think you would be okay. But need to make sure about voltage matching up. Because 4 x 6V batteries in your solar generator may be putting 24V into the inverter. Lots of ways to screw this up. As far as monitoring, if everything is connected properly at 12V, your monitor doesn't know that there are 6 batteries instead of only the 4. Could get more complicated than that if the monitor is a smart one, including a shunt, like a Trimetric setup. But it is probably just a voltmeter.

Really don't have enough info here to give good advice.