Since I started this discussion I have read The RV Battery Charging Puzzle, a blog type website that comes from an experienced and knowledgeable RV camper that full times with solar. Bob certainly does not lack opinions, he is a bit over the top and the website is very lengthy but there are several points he made that struck me.
Before you do anything, purchase a monitoring system for your current power use. Bob likes Tri-metric 2020 and 2025 meters (bogartengineering.com). To him the key readout is the percentage of charge.
Most battery manufacturers recommend charging at a rate of 14.8 volts. Unfortunately most converters peak put at 14.2-14.4
Note: The WFCO WF-8955PEC, which came with my Escape, has a charging rate of 13.6 with a boost rate “bulk charge” of 14.4 Vdc. There are many complaints about this charger never getting into the third stage or bulk charge. The issue with this is you might be unplugging from shore power with a battery that is not fully charged. Some claim a full charge should be 12.6 volts as measured an hour after charging has finished. Bob claims that with the proper charging rate a 12.8 will be possible, most generally it is accepted that 12.7 volts as a full charge. I have found with 24 hours of charging I can get 12.68 volts, beware that this is 24 hours; this is a slow charger so give your unit a long time on shore power before heading out to run on batteries. It is so important to get your batteries full because a 95% charged battery has 10% less usable power in it than a 100% charged one, since you are trying to keep it in the top 50% of its operating range. I do not think the built in charger from Escape gives you a fully charged battery.
“You also need to watch out for those who brag about being charged up by 10:00 or 11:00 AM. They either have more panels than needed or their systems are shutting off early because they are set up wrong.”
As Jubal has pointed out, and Bob would agree, the choice of wire, lengths of run and methods of connecting can have significant influence on speed and quality of solar.
Bob also talks about batteries, inverters, monitors and much more. If you want a strong opinion that appears to be unbiased (from a sales perspective) this could help maximize your solar experience.
Paul and Janet Braun
2003 Toyota 4Runner V8 now 2012 Toyota Sequoia V8
Escape 19' 2010 now 2014 Escape 21'