New member with a battery connection question.

[lvav8r]

I just bought a travel trailer that I'm keeping at my off-grid property. I'm planning to get a 100 watt solar kit (no, not HF) or assemble a similar system that I can add another 100 watt panel to if needed so as to run the basic appliances, lights plus a small TV without needing a generator. My question is how to connect the controller to the batteries? Might get a generator before next summer to run the ac since I live in Las Vegas. The trailer has 2 fla batteries on the tongue connected to a battery switch with 1, 2, 0 and both positions like a boat. Do I connect to one battery, to the house side of the switch or some other way? I've looked for an answer online but all I find is how to connect batteries in parallel or series which doesn't answer my question. Either an explanation or direction to where to find the answer is much appreciated. Thanks in advance.

Tom in Las Vegas

 

[lvav8r]

I wonder if I posted this in the wrong section? If I don't get any response by this time tomorrow, I'll try a different section of the site.

 

[MPRanger]

What is the brand, model and year of the trailer? Is the battery setup factory install or after market? Have you asked the seller about this?

 

[lvav8r]

Thanks for the response. It's a 2005 Skyline Aljo180LT looks like a factory installed setup to me. Haven't asked the seller about it, he was the second owner and I believe it was like this when he got it. Should be simple for anyone that has more experience than me. I know just enough about electricity and electronics to be dangerous with a soldering iron! I did repair my home TV twice successfully as well as an antenna tuner I bought as a "tech special".

 

[Stepandwolf]

Your application sounds like something more suited for a Jackery or similar. With only one 100w panel, you won't be generating much current under ideal conditions, so a foldable panel you could set out connected to a Jackery will give you the most energy and will manage charging for you.

 

[lvav8r]

I'm not planning to mount the panels so that I can place them so as to always be in maximum sunlight and out only when I'm there. The TV is listed as using 48 watts, I ran it thru a kill-a-watt for 12 hours and it said it used .25 kw. I don't plan to use that terribly much power, mostly want to charge the batteries without a generator. I'll probably get a different TV soon anyway, I saw a new Vizio 24" that the web site says uses 20.8 watts as opposed to the 48 my current one says. I just need guidance on hooking the controller to the batteries. Just to one at a time or to the switch or some other way? Thanks

 

[12VoltInstalls]

Having had 12V fla and solar for a couple summers before ‘upgrading’ —- I’d suggest at least a 200W system. With two grp 27 actual deep cycle batteries that setup will run your lights, a coffee maker, tv… it’ll be a tad ‘tight’ but will do the trick.
Minus the tv but add charging phones, water pump etc I got by on 200W

400W and ~300Ah of batteries and I’m running an electric fridge 24/7 as well, now. (I have 700W of panels but haven’t needed them this summer. Once October passes I’m imagining that I’ll need them)

200W for you will stretch a cloudy day or two. 400W and I think you’ll be a very happy camper.

and imho the 1-0-2-B battery switch: leave it on “both” and charge on the ‘house’ side from the SCC.

 

[Stepandwolf]

If you are going to have portable panels, they will need a controller, and your controller connects to your batteries. You could clip the leads right on the bats in front.

 

[lvav8r]

Thanks 12VoltInstalls, that was just what I wanted to know! I thought I could wire the SCC to the switch but was a little uncertain. You also confirmed what I thought about the size of system I was considering, I was pretty sure I'd need at least 200 watts that's why I wanted to be able to expand it easily. I think I'll get a SCC that can take even more than just 200w so I can expand even more later. I thought about the Jackery or similar but decided against it in favor of spending the money on solar. I'd rather spend up to $500 on a solar system than a lot more on a Jackery that doesn't have the ability to charge without spending even more. I'm just getting started and know its going to be a learning experience. I'll try to remember to post how it turns out. Thanks all.

 

[12VoltInstalls]

Fwiw my original system was the 200W kit from WindyNation. I know some people diss on pwm but the P30L pwm controller that comes with tha kit did excellent for me. The kits I think are still $250-ush and the charge controller will do 500W of panels if you expand in the future. Use a pure/true sine wave inverter and disable the on-board ‘converter’ so it doesn’t waste your power and kill the batteries. NEVER let the batteries dip below 12.04V if you want them to last.

 

[lvav8r]

OK, I've decided to put together a diy 200w system with 2 HQST 100w panels and a 40a mppt SCC so that I can easily add on more panels later. I'd like to use the Santan Solar used panel but size and space are an issue. If later I decide to mount something to the roof, then a larger panel could work. I'm just going to use the onboard converter and batteries for now but may change to an inverter later or even 24v. I'm a proud coffee addict but don't need any electricity to make a pot full. I just heat the water on the propane stove in a tea pot and pour the water over the filter basket in the Mr. Coffee and it comes out the bottom just like it usually does. You can even cut the cord off if you want! Thanks for all the comments.

 

[12VoltInstalls]

Hmm. But you ‘could’ make coffee for free if you don’t cut the cord. No propane.
I make coffee in the morning- the batteries don’t know it with the sun up.