Charging leisure battery from car

[Thomas-the-Terrano2]

Sure Ive read that due to voltage drops in the cable and
connector (12S) that the caravan battery gets very
little fro the car. On that basis for several years I didnt
bother with a 12S on car, charging it on mains at home
before a trip.

Getting close to a solar panel to top it up with on extended
hook up less trips, ok could have a genny but don't have
need for high powered mains stuff. The gen could charge
a battery too, think some make about 8A.

Wondering what could get from car on an occasional
basis, don't fancy charging in boot travelling now and
insurance implactions of a 2nd battery under bonnet, so
thinking good cable off car battery or alternator.

How much could a 110Ah leisure battery take to boost
it quickly, thinking car's battery soon gets charged
after being flattened.

[dan]

The battery won't take a whole lot of charge when travelling due to the other electrics dragging the excess alternator charge down.

These will mostly be the fridge, which will be 12v when travelling, and also the lights. With none of that running, it would receive the charge. Would be easy just to charge when on hook-up and charge before you leave, as this will give the battery a deep cycle charge, which will last circa 3 days without a supply, and the excessive from the vehicle will keep it topped whilst on the road.

Solar's good for topping up, but make sure they are regulated, as some will conitue to charge non-stop and damage the battery.

[(RIP) PLANK]

I assume we are talking about when the caravan is not attached to the car? I would avoid a quick boost for a leisure battery. But if you had a small Generator why not put it on for a n hour or two every evening while you are watching the telly and then your battery need never get low in the first place! You can even take a proper battery charger under one of the seats that will put more back in than the Zig does

I have never, ever, bothered with the 12s connection, nothing is free and you pay in fuel for keeping the fridge cool while you are driving. If you plug it in at home before you set off it will stay cold for hours anyway. Same with the battery, if it is already fully charged then why keep topping it up over a couple of hours drive to your destination?

I know that you know my views on this, but the problem to me is people inventing 'issues' to overcome, the battery goes flat because they have too many accessories!

[Thomas-the-Terrano2]

well only use for 12s battery charge is if was going site to site with
no mains at either end of journey. the fridge is always on max before
leaving home. then on gas if no mains on site.

tbh the 12s on current outfit may well only being seeing use for the
reversing light on 'van. the van also has fancy electrics which charges
the battery from the live pin not the charge pin so senses voltage
hopefully from aternator increasing, assuming it does. it also uses
the habitation pin of the 12s and isolates the vans battery and
interior lights if senses engine is running, hmmm.

personally always thought if didnt have the separate wiring from the
near and off side lights in the 12n we could have had a pin for reverse
and forget 12s...

if i use a hybrid 12s cable with just pin 4 and earth and car engine
running in genny mode what i can expect, even thought of a 12s
socket just for this under front bumper of truck with better wiring capacity.

or jump leads or equiv from car bat to van bat?

would tht be too much of a boost for leisure battery almost set would
have if mounted a leisure on truck permanantly.

dont want to buy a genny. weight and cost, noise, limited times can use
due to noise.

looking at a panel and occasional back up genny mode by trol...

[rustic]

Originally Posted by Thomas-the-Terrano2

personally always thought if didnt have the separate wiring from the near and off side lights in the 12n we could have had a pin for reverse
and forget 12s...

I wondered this for years, but the two reasons I can think of is that some cars have parking lights that can select either left or right side, I remember the vectra, if you left the indicator left or right still on, then that sides side lights stayed on.

The other reason is safety, if there is a fuse failure on the side lights then there will be at least one red light on the trailer/caravan.

Boats are similar to caravans, except they float.
On our boat I have also fitted 3 x 10 watt solar panels, and also increased the charge output on the outboard from 6 to 10 amps. and we are now power happy, but also suppliment the charge with electric hook up.

The next stage is a second leisure battery.
Our power consumption is mostly the hot water shower pump, but also a similar pump to drain the shower. Propex hot air heating etc.
Navigation lights, spot light (6 amps) for late evening cruises.
I have also converted the interior lights and navigation lights to LED to reduce the power consumption.

Last season without the 10 amp coil on the outboard, solar panels etc and LED lights etc we did manage to nearly flatten the battery.

But if we are desperate, we can hand start the outboard to boost the battery at any time though.

For caravan users.Maybe a second leisure battery is the easiest option, charge one in the truck on days out and swap every few days.

[Deleted account DD]

Cant speak in terms of measured voltage drop and current flow but I can tell you that our liesure battery goes from flat or (or close to it !!) to fully charged with no problems at all on most trips we do. Some pretty short

Over the years Ive also tried tried the lights only with no auxiliarys to save fuel and the difference is too small to calculate a few pence for comfort and convenience is exceedingly good value Mr Kipling

[(RIP) PLANK]

Originally Posted by daved

Cant speak in terms of measured voltage drop and current flow but I can tell you that our liesure battery goes from flat or (or close to it !!) to fully charged with no problems at all on most trips we do. Some pretty short

Over the years Ive also tried tried the lights only with no auxiliarys to save fuel and the difference is too small to calculate a few pence for comfort and convenience is exceedingly good value Mr Kipling

It charges so quickly because it's not very flat, you've hardly used any power! I probably would have gone on for weeks with no more charging required!

And i still don't see why you need everything in the caravan powered up when you are in the car? Comfort and convenience in there is courtesy of Jeep surely?

My perspective is probably a little different, as I know most people spend 335 days each year in the house and perhaps 30 in the caravan. Where as I spend 360 in various Caravans and only go in a house under sufferance! My view is that people try to make being in a caravan the same as being in a house - comments?

[Thomas-the-Terrano2]

with you, as said this van is so power dependent, has more function
that our static of 70s. we went weeks on a battery for a floresent
light odd 12v b&w telly, lights were mostly gas, miss them.

[(RIP) PLANK]

Originally Posted by Thomas-the-Terrano2

with you, as said this van is so power dependent, has more function
that our static of 70s. we went weeks on a battery for a floresent
light odd 12v b&w telly, lights were mostly gas, miss them.

you are all gadget junkies

[dan]

Originally Posted by PLANK

My perspective is probably a little different, as I know most people spend 335 days each year in the house and perhaps 30 in the caravan. Where as I spend 360 in various Caravans and only go in a house under sufferance! My view is that people try to make being in a caravan the same as being in a house - comments?

Totally agree! This is why we have to run on the 'safe side' as we are hiring ours to people that are used to leaving the TV on all day in the background, leaving lights on etc, and leaving the power on when they are not using it.

One thing about camping - you soon notice how much water you use, and how much power you consume in a house. Once you turn off what you don't need, the battery would last quite a time!

[Deleted account DD]

Originally Posted by PLANK

It charges so quickly because it's not very flat, you've hardly used any power! I probably would have gone on for weeks with no more charging required!

And i still don't see why you need everything in the caravan powered up when you are in the car? Comfort and convenience in there is courtesy of Jeep surely?

My perspective is probably a little different, as I know most people spend 335 days each year in the house and perhaps 30 in the caravan. Where as I spend 360 in various Caravans and only go in a house under sufferance! My view is that people try to make being in a caravan the same as being in a house - comments?

bloody hell youre going to have to start reading the posts properly mate

I said our battery is often flat or near flat. It regiularly wont light the lights.....that flat. It is now into its 4th year of abuse and shows no sign of giving up.

Like you I have previously always used car batteries, this one is a leisure battery simply because i didnt have a spare car battery around

Best one ive ever had came from a motor factors on the spec of "the cheapest heaviest duty battery you have" that one lasted several years and was sold in working order with the van it was in

Some of the battery theory is hypothesis and bullshit in the practical world

As far as everything powered up in the van Ive no idea what your eon about. The leisure battery is charging ( needs to cos I let it go flat ) the fridge is keeping cold , extrenal lights powered up where req and the alko atc working . thats it

Comfort, well if anyone thinkd 12v only is roughing it i can garuntee you its luxury. Having spend days and weeks at a stretch living in a scrape or bivvied out any caravan is starting to replicate your home

Anyone can slum it

[illy]

Originally Posted by daved

Comfort, well if anyone thinkd 12v only is roughing it i can garuntee you its luxury. Having spend days and weeks at a stretch living in a scrape or bivvied out any caravan is starting to replicate your home

Anyone can slum it

Lol Daved no what ya mean mate, I also had to live in a garden shed for four months in Crossmaglen Northern Ireland till the mortar proof accommodation was finished.

What about 2 batteries though.