2005 Horizon 40AD solar upgrade

We need to know what gauge the wire is going from the roof down to the solar controller, and then on to the battery. (My 2017 Airstream has 10g wire, but Airstream is now putting 8g wire there.)

Bobbo wrote:
We need to know what gauge the wire is going from the roof down to the solar controller, and then on to the battery. (My 2017 Airstream has 10g wire, but Airstream is now putting 8g wire there.)

Thanks for the quick reply Bobbo! That is a good point and a great place to start, I will have a peek at it and post the wire size in the next couple days if the weather holds out.

I do think that changing out the wire for a larger size is something that I could manage to do without having to tear anything out to the point of it leaving any obvious signs that the work had been performed, but that does still leave me needing to know about the capacity or "ampacity" if you will of the other stock components(other than the wiring itself).

Thanks again and I love having this forum where people can share what they have already experienced regarding so many things!

I’ve found the WindyNation wire size chart helpful. Look near the end.

https://www.windynation.com/jzv/inf/choosing-right-wire-size

The model # of the controller is likely how many amps it can handle. By going to a mppt controller (more efficient) and upping the voltage, the wire size becomes less important.

I am still not sure about the current rating of my existing charge controller. from what I can find though, I think it is unlikely to be anything that will work with my upgrade. It is a multipurpose unit made by Ventline and was probably sold by the thousands capable of being nothing more that a bell or a whistle that would cause a prospective sucker, I mean buyer (like me) to be impressed and just have to have it.

The unit controlled everything from tank levels and battery condition monitors to pump and hot water controls, the solar controller being only one small part. My issue now is being able to strip it from the other systems so I can incorporate a separate controller and leave everything else that the unit does in a working state. If I manage that, I may consider running something from the new controller unit to the charge LED in the old one just so it still lights up when charging. I would have added some pictures of my unit as well as a pdf I found online with some limited information but the add image feature here seems a bit beyond my capabilities. The part number for my multipurpose control board is Ventline L5130-02

Thanks again for the help folks!

I'm with lvlog. Up the voltage from the panels by connecting in series. "Stock factory equipment" is probably #10 wire.

running the panels in series with a mppt will alow you to have much more on the same wires, so that somthing to keep in mind when your trying to figure it out.

Thanks guys, I was considering one single 400 watt panel which I have room to mount on the roof. So I take it from the last responses that it might be a better idea to run multiple panels instead?

genemcdole wrote:
it might be a better idea to run multiple panels instead?

It all depends on the wire size to your controller.

genemcdole wrote:
Thanks guys, I was considering one single 400 watt panel which I have room to mount on the roof. So I take it from the last responses that it might be a better idea to run multiple panels instead?

not nessairly, a 400 watt 24V panel with a good MPPT controler is a great starting point and might be all you need depending on how it works for your camping style. but it is also a good starting platform that you could add a second 400 watt panel to it if it isn't quite meeting your needs. I run a single 325 watt panel on my truck camper but I don't run any 110 apliances and it works great. on my 5th wheel I hav 480 watts of panels and while they are good, I am thinking of upgrading.

Steve