rhodesia Report post Posted April 13, 2018 Hello I bought a 2007 Gulf Stream Sun Voyager 37 foot it came with a 65 watt solar panel on the roof the kind that you peel and stick to the roof well anyway I could not find the Solar Charge panel Controller in the motorhome so I had asked the RV tech and he told me anything under 65 watts does not need a solar panel controller because it is wired into the battery system if I wanted more solar panels which I'm looking at 300 watts to put on the roof then he said I would need a Solar panel controller or booster well is this a true statement because it seems strange since a solar panel was installed on the roof you would think there would be a solar panel controller inside the motorhome to view the voltage. instead of viewing the motorhomes panel for battery levels any ideal would be great, thank you for any input. Share this post Link to post Share on other sites
rayin Report post Posted April 13, 2018 I know little about solar systems. That said, Winnebago put a 10W solar panel on the roof of our MH, it only has a small red indicator light that illuminates when in sunlight. It is hard-wired to the house battery bank. I suppose that means a tiny bit of energy is being produced. I do know it's not enough to keep the battery bank maintained, even in full sunlight.. Share this post Link to post Share on other sites
desertdeals69 Report post Posted April 13, 2018 1 hour ago, rhodesia said: Hello I bought a 2007 Gulf Stream Sun Voyager 37 foot it came with a 65 watt solar panel on the roof the kind that you peel and stick to the roof well anyway I could not find the Solar Charge panel Controller in the motorhome so I had asked the RV tech and he told me anything under 65 watts does not need a solar panel controller because it is wired into the battery system if I wanted more solar panels which I'm looking at 300 watts to put on the roof then he said I would need a Solar panel controller or booster well is this a true statement because it seems strange since a solar panel was installed on the roof you would think there would be a solar panel controller inside the motorhome to view the voltage. instead of viewing the motorhomes panel for battery levels any ideal would be great, thank you for any input. That small of wattage does not require a controller and it is only good for maintenance charging. If you want to rely on solar to replace used electricity you would need several hundred watts and 4 or 6 6 volt deep cycle batteries. I have 800 watts with a MPPT 40 amp charge controller and 6 AGM batteries and a 3000 watt Xantrex inverter. With bright sun light this system will charge 38-40 amps with low batteries and taper off as the batteries are coming up on the charge. Share this post Link to post Share on other sites
kaypsmith Report post Posted April 13, 2018 The mathematics are pretty simple. With 12 volt panels, divide the wattage by 12 to decide what size controller you really need, 1200 watts divided by 12, needs a 100 amp controller to get maximum usage of the solar panels. And as DD69 says, those amps need to feed adequate battery supply, which in turn will power the inverter to convert 12 volt dc to 120 volt ac, the larger the battery bank is, the longer you will be able to draw at 120 volts. Your 65 watt solar panel is producing barely 5 amps to the battery bank, actually a pretty good battery maintainer, but that's all. And the 10 watt is less than an amp, not even a good battery maintainer, but is helpful if there is no parasitic draw. DD has a good system for boondocking, with careful monitoring of electric needs could stay for long periods with no other means of electric supply. Share this post Link to post Share on other sites
rhodesia Report post Posted April 13, 2018 2 hours ago, kaypsmith said: The mathematics are pretty simple. With 12 volt panels, divide the wattage by 12 to decide what size controller you really need, 1200 watts divided by 12, needs a 100 amp controller to get maximum usage of the solar panels. And as DD69 says, those amps need to feed adequate battery supply, which in turn will power the inverter to convert 12 volt dc to 120 volt ac, the larger the battery bank is, the longer you will be able to draw at 120 volts. Your 65 watt solar panel is producing barely 5 amps to the battery bank, actually a pretty good battery maintainer, but that's all. And the 10 watt is less than an amp, not even a good battery maintainer, but is helpful if there is no parasitic draw. DD has a good system for boondocking, with careful monitoring of electric needs could stay for long periods with no other means of electric supply. Thank you that information really helped me thought I was missing something in the motorhome or the solar panel was on the roof to make it look good I have 2 12 deep cells for the coach and 1 regular 12 volt for the coach engine itself they are all located in front of the motorhome. The RV tech said I could go higher than 300 watts of solar because I have allot of space on the roof to add more panels but I don't want to look like I'm prepping for the end of the world, LOL again thank you for the information Share this post Link to post Share on other sites