how to charge the caravan batteries

[Gullible]

Hi,
I have 2x 100 Ahr gel batteries in our caravan and I'd like to charge the batteries while towing the caravan with our D2. Currently we do not run anything from the batteries while we are towing, but I'd like to change that and put a 2way fridge in the caravan.

So I was thinking about putting a dual battery charger in the car with an anderson plug under the rear of the car to connect to the caravan. I also have a freestanding battery that we take camping and it would be good if we could charge that up every now and again when we go for day trips.

Any tips on how to run the cables under the D2 to the rear bumper and then into the back of the car? I'd rather not just put the cable through the door as it is quite a tight fit and would end up pinching the cable.

[Pedro_The_Swift]

Ok,, first up the car will charge all your batts on a trip,,(given good cable),


second.. Think Solar;)

For a couple of hundred bucks the van is totally self contained.

[Gullible]

It is funny you should mention solar. I was thinking that would be good way to go. I do not know much about it. Would it be better to have the panels fixed to the caravan roof so it charges while on the road? or have them independent so the caravan can be parked in the shade but the panels can be in the sun?

Our trips in our caravan are fairly fixed. We dive to our block of land by Grafton and stay off grid for 3-4 weeks before driving home. On the trip up and back we stay at powered sites.

the more I write this down the more sense solar makes.

OK, how do I make an independent solar set up that I can plug into my caravan and unplug from my caravan to plug into other batteries (like the ones in the shed). And how many solar cells do I need to keep the batteries happy while running a 12v fridge?

[vnx205]

Would it be better to have the panels fixed to the caravan roof so it charges while on the road?

That is what your alternator is for. :)

Surely you only need the solar for the times when the vehicle isn't running.

[Gullible]

That is what your alternator is for. :)

Surely you only need the solar for the times when the vehicle isn't running.

Yes, but that brings me back to the issue of setting up a duel battery system which would only be used on the way up and down.

Ideally I'd have both but thats not financially possible.

[Yorkie]

Just run cable from the starter battery to the Anderson plug at the rear, fused of course.
On the van if you think you might want to run a fridge whilst moving fit a fridgeswitch which only allows current when in motion. :)

[drivesafe]

Hi Gullible and there are a number of different ways to set up your tug and your van, but you need to know how you intend to use your setup before deciding on a DBS to suit your specific needs.

For instance, are you likely to drive for an hour or more when you do your day trips?

Do you have a small inverter and small battery charger?

Solar is the best setup but it is the most expensive and is weather dependant.

There are other setups that can give better results for less money.

[Gullible]

We have a set routine. We take 2 days to drive from Canberra to Grafton stopping at a powered site on the way. We park the caravan in a field with a shed and leave it there while we plant trees and take day trips to the beach.

The day trips are usually less than 45 min driving each way.

We try to stay on the land for 3-4 weeks at a time.

We have a generator that we run if we need the air-con on.

We do not have a dual battery set up in the car and do not run any auxiliary equipment in the car.

[Pedro_The_Swift]

That is what your alternator is for. :)

Surely you only need the solar for the times when the vehicle isn't running.

not really,, you'll find a properly set up system is totally independent of the vehicle.
one less plug, one less worry.

of course for you people that live where the sun dont shine---;):D

I'd be interested in your ideas Tim:ohyes:

[Vern]

Going to jump in on this thread if that's OK gullible, I have a similar set up, two auxiliary batteries in the car (spiral cell optima, 3 Inc starter), and a 100a/h in the camper, which I may add another.
I run time usi160 duel battery system with a 90a alternator (will upgrade this one day). I have solar for the camper and that has a 240v cetek charger.
So what's the best, quickest way to charge all this, some times you may drive all day, sometimes you may drive for 2hrs.

[drivesafe]

Hi again Gullible, and with your current operations, you would probably gain the most advantage by increasing your solar and use the gen on those days you don’t get the sunlight you need.

Being as you plan on doing regular day trips, if you had a dual battery setup you could use your tow vehicle’s batteries to top up your house batteries via an inverter and a battery charger and probably not need additional solar.

[Gullible]

Being as you plan on doing regular day trips, if you had a dual battery setup you could use your tow vehicle’s batteries to top up your house batteries via an inverter and a battery charger and probably not need additional solar.

Ooo, Id never thought of being able to do it that way round.

[drivesafe]

Hi Gullible, this type of setup is only good if you do some daily driving and while it can top up or even recharge the house batteries, it is something that only needs to be used if your existing solar setup is not keeping pace with your usage.

Even if you do a daily drive trip every day, you might find you only need to use this setup to top up your house batteries once every three or four days.

The advantage of using an inverter/battery charger setup is that while you are topping up or charging the house batteries, your tow vehicle batteries do not have to be fully charged to be able to fully charge the house batteries.

The setup is also easy to do. Just fit an Anderson plug to say a 300w inverter and the run an ordinary 240VAC extension cord over to a 10 amp battery charger in your van.

Job done.

The smaller the load placed on a lead acid battery, the greater the amount of energy you can get from that battery and at the other end, the slower you charge a lead acid battery, the more efficient the charge is so you need less energy to fully charge the batteries.

So even though there is a loss through the inverter/battery charger setup, by using a small inverter and battery charger, you increase the efficiency of this type of setup.

On the flip side, if your solar is keeping up with your daily power usage, you can always use it to top up your tow vehicle batteries, keeping them in a higher state of charge just incase you get some bad weather days.

This type of setup gives you a win, win, win system.

[Hoges]

I use this setup to charge deep cell battery in a camper trailer. The second battery in the vehicle (charged by Drivesafe's magic SCR80) feeds the inverter, but the inverter and (5 step 7 amp ) charger are housed together in an (electrically) insulated vented enclosure (to dissipate heat) (12V in; 12V out) in the camper. This minimises potential risk of 240V electrocution in case of accidents... I see some 4WDs are now offering 240V outlet as a built in option in the vehicle... bit of a worry? I am still edgy with the thought of a 26kg battery breaking loose in the rear of the P38 so need to think of a better way to restrain it... must be an age thing:angel:;)

[TerryO]

We have two x 135w Kyocera panels permanently fitted to the roof of our van and two x 100 amp AGM battery's in the van. A real bonus from it is that we do not need to carry a genie any longer and while we can charge the van battery's from the vehicle we never have had to since the solar was fitted. So since fitting solar we have never had power problems mind you we don't have a fixed compressor fridge we have a 3-way, but we do have a 60L chest fridge that we always use when camping. To say we are power hogs would be an understatement as we use fans, TV, stereo etc in the day time as well as night plus lots of lights etc plus we normally plug in at least one other chest fridge each day while camping with friends as they don't have adequate solar to charge their battery's up and run their fridge and they get sick of running the genie every bloody day.

If you had a large (over 150L) compressor fridge then to do it properly you would need over 400w of panels and a couple of decent sized house battery's at least.

We don't tend to drive very much while camping so wouldn't be interested in trying to charge battery's up everyday and then go back and charge up the house battery's, seems like hard work and means you have to drive every day to keep your battery's even 3/4 charged. The way we have it set up you don't even think about it, the solar just charges the battery's up to float level usually by 9:00 am most mornings in summer. Then we can use power all day and it just keeps charging as you use it.

Personally I wouldn't ever be without lots and lots of solar on a van because even in bad weather you often still get a reasonably trickle of power to charge your battery's. Plus if your panels are fitted at least 2" off the roof, which is recommended so they don't get to hot in summer, then they keep the van considerably cooler on hot days and much quieter inside when it rains.

By the way for cooling on hot days and nights check out Cerafamo Sirocco gimbal fans, they are near enough to silent and really work well in keeping a van cool. The best place to buy them is through boat chandlers in the USA via the net, they are nearly half the price of buying them here. Good luck with it.

[Pedro_The_Swift]

These really are the ducks guts for vans,,
https://www.aulro.com/afvb/images/imported/2014/07/290.jpg
timer, 3 speeds, and the best bit is they only draw .4 of an amp:cool::cool:

[ozscott]

I did a fair bit of looking and went the Fantastic for the Van and boat. Still made in the US. Very quiet and powerful.

http://www.campingworld.com/shopping/item/fan-tastic-endless-breeze-12v-fan/38132

[ozscott]

I like the a RedArc Dc to Dc charger in the van, with a a Full River in the Van also. Anderson plug from the Disco to the redarc in the Van. Red arc charges the van batt fully and also I have same gauge wire going from Anderson to the 3 way fridge...ie 3 way being powered by the truck with a motion detect Fridge Switch running interference at the fridge. Wicked set up. When I get to camp site, just disconnect the Anderson plug from the truck and plug in 160w portable solar panels and the redarc senses the change and commences charging the van batt as an MPPT solar regulator.

Cheers

[Gullible]

Ho, ho, ho.
I've just ordered the 15 Amp regulator from this mob
Solar for Motorhomes and Boats (http://www.sunworks.co.uk/MotorhomesandBoats.html#SB1C_SB2C)

It looks just what I need, and with the added advantage of not being made in China. :)

[Gullible]

Next dumb question.

If I have a 15 Amp controller that uses <3.5 Amps. What is the larges watt solar panel can I connect?

I keep hearing conflicting advise about whether the solar panel will produce more or less watts than it is rated for. I am confused what panel to get, anywhere between 160-230 watts is what people keep trying to sell me.

[drivesafe]

If I have a 15 Amp controller that uses <3.5 Amps.

Hi Gullible and not sure what you mean by this?

While you are highly unlikely to get the maximum wattage out of any panel, I would suggest with a 15 amp solar regulator, you keep the total wattage under 200w.

[TerryO]

Be aware that many solar panels are also not meant for charging van or car batterys, house panels are normally 32 cells and they don't provide enough voltage to get the batterys up to float even if they are huge in size.

If your going to buy a panel no matter how many watts it is make sure it has 36 cells and get a decent regulator like a ProStar etc.

[Gullible]

I was thinking about 200 watts would do me so I'm happy to go with that.


Be aware that many solar panels are also not meant for charging van or car batterys, house panels are normally 32 cells and they don't provide enough voltage to get the batterys up to float even if they are huge in size.

Now I'm really confused. I thought volts were volts? Most panels say they are 12-24 volt panels.

How many volts do I need to charge a 12 volt battery?

[TerryO]

Our caravan has 2 x 135w quality solar panels fitted along with 2 x 100 amp AGM battery's and that is more than I need even though we use lots and lots of power through on average 4 LED lights, fans, water pumps, stereo and TV and we have our 60 litre chest fridge plugged in day and night and most days the solar regulator shows the battery's are full and the regulator is on float by between 8:00 am and 10:00 am even on cloudy days.

A well set up solar system makes camping really easy, from what I understand a good quality 36 cell solar panel when charging can run up at around 17 volts or so. When a battery is charged and the regulator is at float level then it shows around 13.4 volts from memory.

Our van only gets power from the solar panels, it is far better if your panels are permanently fitted to have them as the only power in even when driving.

I freely admit I am no expert on this but from the little I know and the system I have now had fitted once I found out what was needed to the van I am a total convert to solar for camping and vanning.

[Gullible]

What make and where did you get your solar panels from?

There is such a large variation in price I do not know where to start.

[TerryO]

I bought Kyocera 135w panels, three years ago they were about $1,400 each, now they are about $400 or so if you shop around.

Why not drive up to Goulburn and have a look at our set up? More than happy to show you it and how it works.

[Doc130]

I got Kyocera panels ( 280watts) , they are worth every cent!!! You get what you pay for

[drivesafe]

Hi Gullible, for what you are planning to do with your Jayco, solar would be, by far, the best way to go.

BUT, you do not need to get 200w of solar right from the start, you would probably be better to get just an 80w panel first and see if it meets your needs.

Remember, when you go on a trip, if you have been maintaining house battery properly, between trips, it will be in a fully charged state when you leave home.

So your solar panel is only needed to replace what you use each day plus a little extra, to cover you when the suns not shining.

It is not there to fully charge a low battery every day.

So if you start with something like an 80w solar panel, you may find it meets your needs.

If it doesn't, or if your usage changes, it is a simple matter of just adding another panel ( or another battery, or both ).

One thing I would recommend, make sure you connect the solar panel, via the regulator, to the battery with decent size cabling, and this is one of those areas where oversized is a good thing.

[TerryO]

One question no one has asked yet is what size 2-way fridge are you thinking of fitting to your van? And is it a chest or a upright? Depending on that will make a big difference on what size system you will need.

The trick is to do your research and spend the money once, its common to hear story's about people who try and cut corners to save bucks and end up with a system that doesn't work and a whole lot of wasted time and money and horror story's about wasted trips because the food went off and worse still the beer was warm. ... ;)

[drivesafe]

Hi again Gullible and once again, there is no need to go over the top until you test what you have already got and see where it may need improving, if it actually needs improving.

BTW, there is an excellent solar specialist company in Grafton, and if you get set up on your block and find you have any queries or short falls with your system, call in to Grafton City Batteries.

They are just off the main street in Grafton, at 127 Fitzroy Street.

I have been dealing with Grafton City Batteries for the last 15+ years and they are specialise in RAPS set ups, large and small, and they know what they are doing.

So they can give you GOOD advice, and supply you with anything you may need while you are up that way.