More solar questions

time2roll wrote:

GATJcampers wrote:
With no load on the rv and the batteries still connected I set clamp to DC amps and got .45. Batteries still at 12.1. I understand you say it can take days but I've done that and they are just not charging. I'm sure some of that is my lack of understanding but it just doesn't seem like the panel is any help.
I do have a volt meter also.

If you remove the panel from the battery and short the panel terminals together then what is the amp reading on the meter? s/b close to 5 amps at noon or the Isc rating.

MrWizard pointed this out.
DO NOT SHORT THE SOLAR PANEL WIRES OUT. Do not connect the solar panel positive to the panel negative, this will destroy the panel. The guy did not mean to "short" anything, rather to put a multi-meter on it, and "short" is not the correct term…. But if you just measure the voltage straight off the solar panel you should see 20 volts in good sun. If less than 18 then you probably have a bad panel. If less than 12 then it is trash.
Always use a good charge controller, not the $12 ones. You will spend $80 or more. Sun Saver makes one I have been happy with, and it has some heft to it.

The batteries from an auto parts store are almost always decently charged, not sure about Sam's Club, probably they were charged at the factory and never again.

Always get the newest batteries that you can find. Always get ones of the same age if you are running in parallel (for 12 volts systems), for 6 volt in series this is not an issue.

One 100 watt panel is enough to keep batteries charged, but not a lot to boondock. If you plan to use DC power off just the solar consider at least 200 watts, 300-350 if far north, cloudy/rainy a lot, or in the winter (low sun angle), or have kids that constantly charge devices.
If you plan to use an inverter and run a lot of household things then you need more…