12v power.

[GedsJeep]

now, having sold the caravan and gone back to a tent i am looking at power options.

i have a 240v hook up for the new tent.

but sometimes i wont be near a hook up.

so....

i was looking at a 12v light, something like this...

http://www.worldofcamping.co.uk/kampa-sabre-150-led-12v-awning-tent-light-3649?nosto=nosto-page-category1

now, i have a leisure battery, so if we aint on a hook up we can still use it.

but, how to charge the battery?

the car has dual 7 pin connectors at the towbar and heres the question...

does the aux on the 7 pin charge the battery, or does it just supply the power to the caravan to charge the battery?

IE, could i put the battery in the boot, run the 7 pin aux to the battery and charge it as i drive?

Ta

[1958steveflying]

The 12V supply to the caravan is usually just to run the fridge directly from the car, having said that if you connect it to a battery it will charge it. Gassing of the battery in the boot could be a problem !

[Tony]

We've gone for these for our (massive) tent, much cheaper and plenty bright:

http://www.ebay.co.uk/itm/310983759654

As well as a couple of G4 sockets and 1W or 2W leds which could potentially be left on overnight.

We're just charging with solar, though I don't see why you can't charge from the car when running around.  Potentially could just hook it up to the cigarette lighter socket which is only live with the ignition on.  May want a car headlight bulb in series to stop it drawing a huge rush of current though?

I've got a brand new pair of quick release battery terminals (round ones, car style) which you can have for a fiver delivered if you want?

[GedsJeep]

just ordered one of them, cheers tony 

and yes, interested in the terminals thanks.


just seen one of these, http://www.ebay.co.uk/itm/like/111442384271?limghlpsr=true&hlpv=2&ops=true&viphx=1&hlpht=true&lpid=108&chn=ps&device=c&rlsatarget=&adtype=pla&crdt=0&ff3=1&ff11=ICEP3.0.0-L&ff12=67&ff13=80&ff14=108&ff19=0

could put it in the boot power plug and charge it that way possibly?

[Tony]

This might be of interest to you for camping too?

Charge your phone direct from the lead acid:

http://www.aliexpress.com/item/Motorcycle-USB-Powerport-12V-2A-Dual-Charger-for-Smartphone-Android-Phones/32313007887.html

[photoman290]

i live more or less outside all year. no mains. for basic stuff like camping i would use head torches. if you get the ones with 2 lithium cells they last ages.
 what i do is get old laptop batteries and use the cells out of those. usually there is only one or 2 dead cells. charge a few up at home and you will have light for weeks. just be careful about shorting them though.
you could use them as firelighters in a pinch, just stay downwind of the fumes. the other option is led tape lights. those 7 amp hour sla batteries rossey is selling last around 5 days running a whole string. i am using 3 of them in the yurt at the moment. a lot easier than lugging a car battery around. safer too, you can charge them from the cigar lighter socket with the right charger.
why am i telling a lighting tech all this??

follow spot on the roof to light the way to the bog?

[GedsJeep]

 

would keep us warm too.

i have the tape lights in the garden and they work great, but i wanted something with all the contacts ect isolated to preserve the tent just in case (its just cost me best part of a grand)

the other reason i wanted a car battery was im going to be running a cooler box too.

so, i think ive developed a plan...

i already have a mains supply and rcd kit, i have an oxford battery optimiser and if my nephew can run fast enough i will have a car battery.

so, when on hookup, the oxford can charge the battery which will run the cooler and the lights.

when no hook up, i will buy a solar charging panel and the charger above if that cant keep up.

they have fast chargers in the car for their phones, so can make do with them.

i may have a plan......

[GedsJeep]

more stupid questions...

solar panels, is there different ways of measuring the output?

some seem to be 1.5w, and some 20w for roughly the same sort of price

whys that?

http://www.ebay.co.uk/itm/391147761278?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

http://www.ebay.co.uk/itm/161752575550?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

would the 20w one be ok?

[Tony]

It depends what you want to use the power for. Just lighting or lighting + small fridge?  How many watts of light and for how long?

[GedsJeep]

its to charge the 75ah leisure battery.

which will run this....

http://www.leisureoutlet.com/caravans-and-motorhomes/Electric-Coolers/Campingaz-Powerbox-Classic-Cooler.html?gclid=Cj0KEQjwz6KtBRDwgq-LsKjMk9kBEiQAuaxWUqXEUn_T0OU_6dypcGJTrAZTe-z_6ixv1afF7XrCHjQaAtlY8P8HAQ

and a couple of them lights you put me on to..

i also have one of these......

http://www.ebay.co.uk/itm/271928695923?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

the plan is to run the fridge and lights from the battery.

when on hookup, this will be connected so charging aint a problem.

http://www.ngales.com/products_info.asp?id=229&type=accessories&cat=10&sub=&rge=&kw=&man=

when off grid, the plan was to use the solar panel to charge and the jump start lead if the battery ran down.

does that make sense?

[Tony]

I've tried to find figures for the power consumption on the coolbox.  Some say it draws about 4A but cycles, one guy ran his off a 125Ah battery with no other load and it ran for two days, which works out about 2.5A average.

Of course not a problem if charged from an electrical hookup or the car because they provide plenty of juice.

I guess the way to look at it is that the fridge will take about 60Ah a day
2x 9w lights for 4 hours is 6Ah a day
A 20W panel at full tilt for 10 hours will charge about 13Ah a day

So the panel should keep up with lights alone but not much else.

If you wanted pure solar for lights and fridge I'd be looking at getting 160W of solar, it's the fridge that is the killer.

BTW I was testing those 9W strips last night, boy they are bright!

Some more bits that you may find useful:

http://www.ebay.co.uk/itm/251875766781 (2.5mm2, good for many amps)

That cable JUST fits these connectors, if the yellow seals on cable entry are trimmed down a bit:

http://www.ebay.co.uk/itm/251937035285

And one of the two cores will fit these, only need to switch +ve anyway, the negative just loops past:

http://www.ebay.co.uk/itm/291294874659

I'm making up a bunch of sections of wire with connectors, Y pieces and switches with a connector either side so it's modular and I can change it around as we fancy on-site, without having to do any more soldering/crimping

[photoman290]

have a look at bimble solar they have a 235 watt unframed panel for £90 delivered. i have just got 3 of them. seal the edges with ally tape,and get the terminal box with the diodes. extra £7. as long as you keep the fridge on that should not boil the battery so you wont need a charge controller. they are basically a sheet of laminated glass so fairly tough as long as you are careful.

[GedsJeep]

tony, thats ace mate, i already had them connectors on watch for something else!

photoman, thats a bit more than i want to spend, but cheers anyways.

[Tony]

Excellent panel prices, what do they mean by grade B?

[photoman290]

minor cosmetic damage. a few scratches ect. mine have them marked with china graph. if they were not i wouldn't have noticed. what i am doing is fitting them over my old panels,which have died. they had broken glass, but lasted 5 years outside in cornwall. the new ones  are the same size so i am just taping them to the old frames and making a holes in  the old ones for the terminal box. it does make them heavy but as they are on the ground anyway that is not a problem.