What size solar collector?

PonchoLasagna · April 2017

We expect to be camping with our T@B S for 3-5 days, sometimes boon-docking. Would 80 watts be sufficient?

rfuss928 · April 2017

Lots of variables but the general consensus on on the small trailer forums I visit has been 100 - 120 watts minimum.

lapowers57 · April 2017

I have found my 160's are a good compromise between capacity and weight. I would not go below 120 if boon-docking for several days using a stock battery. In fact if boon docking on a regular basis I would upgrade to at least a 100 ah battery.

newell · April 2017

Thanks folks. Our dealer recommended an 80 watt. I'm not sure how much experience he's had with actually using a solar collector out of the showroom. Since we're brand new at this we didn't want to get more than we needed but we sure don't want to get less. Judging from the comments here and the you tube videos out there, I think 80 watts would have been a mistake.

JandJ92010 · April 2017

I use two 12 volt batteries in parallel, My 120 amp. (2-60's) panel keep them charged up just fine.

JohnDanielsCPA · April 2017

I have two six volt batteries (225AH capacity) and use a 200 watt panel. The general rule seems to be be to match the wattage to the batteries. In other words, 120ah battery pairs with a 120 watt panel; 200 ah batteries to a 200 watt panel; etc. If you are going to boondock (which is, presumably, the reason to have a solar panel), an 80 watt panel would never work, because you really should have more battery capacity anyway. It may work as a trickle charger to keep your batteries topped off when not in use.

newell · April 2017

Hopefully this isn't too stupid a question. When the battery(s) are fully charged by the solar panels, does the 12volt appliance run off the battery or the solar ?

wizard1880 · April 2017

For the zamp at least, it's always monitoring the battery.

Here's a scenario: If an appliance comes on that takes less amps than the panel is capable of, it will run directly off the panel. But, If the appliance takes more, it will consume all the panel has to offer, and the rest comes from the batteries. When that said appliance turns off, the panel will then top off the battery of what was used.

I hope this makes sense. I'm sure there's better analogies that could explain it.

Bill_Cochrane · April 2017

I am really terrible at this stuff so if I may I will ask a question too. Given that we anticipate a day or two boondocking followed by a campsite with 120 V supply, would the Go Power system in the link below be a good choice for the battery that comes with the 2017 T@B? I believe it matches the advice given 120 W for the 12 V and the controller would attempt to ensure the battery is properly charged under all load and charging conditions. That is, it would not over charge or boil the battery. But it may not be a large enough charging system if I ask too much of it; lots of lights, TV, radio etc etc. Do I have this correct?

https://www.amazon.ca/dp/B009MIPH4K/ref=wl_it_dp_o_pd_nS_ttl?_encoding=UTF8&colid=V6WFKC26O1LB&coliid=I2I6CQDXR2LAFD

HR_Taly · April 2017

newell said:

Hopefully this isn't too stupid a question. When the battery(s) are fully charged by the solar panels, does the 12volt appliance run off the battery or the solar ?

No stupid questions, @newell! We all had to learn somewhere ourselves. If you don't ask, you'll never know and learn.

Nothing "runs" off solar, solar only replenishes the "juice" in the batteries. The battery is what runs your 12v items and appliances. How you replenish that battery when it drains down is where solar (or a generator) come into the picture.

That's why it's important to match your battery with your solar system. You could have 2,000w of solar, but if your battery is only a dealer-provided around 50Ah, it would be overkill. Likewise if you have 500Ah of battery but only replenishing it with a 80w solar panel, it would take a loooong time!

So that's an oversimplification, but hopefully helps. The reason it's a puzzle is because everyone camps differently. Are you only going out on the occasional weekend or longer term? Do you use the 12v appliances a lot (watch a lot of TV, etc?). That's why there's no right answer. But if you comment detailing your camping style, you'll get lots of real-world advice (and opinions!) from people on what might be the most effective and cost-efficient set up for you!

newell · April 2017

We're picking up our 2017 T@B S this week. I'm embarrassed to say that I don't know how many ah battery the dealer is providing so I better give him a call pretty quick and if it's only a fifty, I'll tell him to keep it. Here is the next question. How large a battery bank can I fit in the space provided in the enclosure? Also should I limit myself to that enclosure or are there better options?

HR_Taly · April 2017

Keep in mind that many people successfully boondock on the stock battery (the battery is placed in/determined by the dealer), if you are only going out for a weekend without hookups you would likely be fine with that (with a bit of solar of generator to top up, although some people don't need to do that!). Batteries are expensive! But they are also easy to upgrade later. You might want to go ahead and try it with whatever your dealer gives you to see if it works for you (as long as it's a proper deep cycle battery).

As for fit - Some searches of the forum will give you information on what people have fit in the stock box. I think that two 6v won't quite fit in a non-Outback tab stock box, but then again, I think I've seen a recent post where someone has done it. Searching this forum is an excellent resource.

If I were you, unless you are doing extensive boodocking (multiple days at a time), I'd ask your dealer what battery they intend to put in (they may call it a "Group xx battery"). Then ask how much extra for them to upgrade that into something a bit better (maybe from a flooded vs AGM battery). If the cost is reasonable, go for it. If you go out for 4+ days at a time consistently, you might want to put some thought into investing money into a larger battery from the start. If not? A combination of stock (or slightly upgraded stock) battery and a portable solar panel will likely serve you very well and very cost efficiently.

jkjenn · April 2017

HR_Taly said:

Keep in mind that many people successfully boondock on the stock battery (the battery is placed in/determined by the dealer), if you are only going out for a weekend without hookups you would likely be fine with that (with a bit of solar of generator to top up, although some people don't need to do that!). Batteries are expensive! But they are also easy to upgrade later. You might want to go ahead and try it with whatever your dealer gives you to see if it works for you (as long as it's a proper deep cycle battery).

As for fit - Some searches of the forum will give you information on what people have fit in the stock box. I think that two 6v won't quite fit in a non-Outback tab stock box, but then again, I think I've seen a recent post where someone has done it. Searching this forum is an excellent resource.

If I were you, unless you are doing extensive boodocking (multiple days at a time), I'd ask your dealer what battery they intend to put in (they may call it a "Group xx battery"). Then ask how much extra for them to upgrade that into something a bit better (maybe from a flooded vs AGM battery). If the cost is reasonable, go for it. If you go out for 4+ days at a time consistently, you might want to put some thought into investing money into a larger battery from the start. If not? A combination of stock (or slightly upgraded stock) battery and a portable solar panel will likely serve you very well and very cost efficiently.

Good advice. Most folks who are we to RV camping need to go out camping a few times to figure out what their style and needs are. You might find that you are almost always at electric sites and don't need anything different.

lapowers57 · April 2017

Let me say that I do not like having to make mods to my camper so I try to keep things simple. Unless something has changed this year then the T@B comes with a group 24 battery. The largest group 24 battery I found was a 100ah battery from Trojan. Someone else may have found something slightly bigger. My dealer gave me a 55ah battery and it was a combo deep cycle/starting battery. I would recommend getting the biggest group 24 battery you can find it will serve you well. Anything larger and you will probably need to modify the T@B to make it work. If you are use to tent camping then you can survive a three day weekend with this size battery if you are very conservative with your electric use. We did this several times while waiting for our solar panels. If you combine this with a 120 watt or larger set of solar panels, you should be good for most trips that you will want to take. I like the Zamp panels, they work well and the T@B is set up to use them without mods. I also don't carry a generator because I don't like having to haul and store it and a gas can. Don't over think it, just go camping and have fun.

BirdieJane · April 2017

Looks like the Zamp 120 watt is about the same price, the trailer is already wired for it. http://http//www.dyersonline.com/zamp-portable-120-watt-solar-kit.html#

phulishcat · April 2017

The stock front storage box on the t@g and t@b will fit a group 27 without modification. It fits at an angle and you would need a new battery box but most dealers have both on site and some will upgrade it to the group 27 for free. Just my experience.

pthomas745 · April 2017

The Zamp connector "reverse polarity" question and the confusion around it has launched a million forum threads all over the internet. It threw me, too. But what sounds like electrical engineer voodoo is really just a safety measure, and it makes lots of sense. Go read Michigan Mike at the old little guy forums, where he explains what this "reverse polarity" is all about. It is simple, believe me.

http://littleguy.vanillaforums.com/discussion/4885/zamp-solar-panel-connections-explained

I have a 5 year old 100 watt Renogy panel that I bought for an emergency earthquake preparedness kit. I have a very small 35ah battery to go with it, and I've used it for tent camping and simple charging tasks. (Still waiting on the earthquake!) It was/is a good learning experience.

When I bought my Outback last October, I was thrown by the "reverse polarity" thing. So, I just used a cable with alligator clips to connect the solar from the controller to the Outback's battery. Dead simple.

This worked just fine, and needed no modifications at all. Later, when I read the thread from Michigan Mike, I figured out the trailer's Zamp connector. It is a massively easy fix, believe me.

Nothing against the Zamps or any other "kits" out there. They are beautiful and elegant and simple. But after 5 years with my panel, counting a couple of improved solar controllers and the battery I killed in the early learning stages, I am nowhere near spending the amount of money those suitcases cost.

And, to answer the original question: I have a Group 24 battery, a 100 watt panel. In five days in Death Valley a few weeks ago (plenty of sun, of course!) I had more than enough power for laptops, camera batteries, etc. I ran the Fantastic Fan all day.

newell · April 2017

Does anyone have a photo of a typical 2 battery installation either under the propane enclosure or externally?

newell · April 2017

Another chapter to our story, we are heading up to northern Maine this summer for a couple of weeks and at least one of the Maine state parks we'll be staying at does not have hook ups. We need to get comfortable with our boon docking skills before we head up there.

pthomas745 · April 2017

There are many threads about two battery setups...here is one using 6v, with some pictures on page 2.

http://tab-rv.vanillaforums.com/discussion/4313/dual-6v-batteries/p1

newell · April 2017

Okay, we bought the Interstate SRM-29 106ah battery at a 5 amp draw. It has a 200 minute reserve at a 25 amp draw which is twice the reserve of the SRM-24 that was supplied for the camper. I think we will have plenty of power. Thank you everyone for you help and advice.

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