Leisure battery via alternator

A very basic split charger system is just a 100A solenoid that turns off when the alternator is not running.

So to install.

Disconnect the positive from your starting battery.
Run a cable between the positive of your starting battery to the positive of your leisure battery without hooking anything up.
At a convenient spot close to the starting battery cut the cable and then hook up the solenoid as per the instructions that came with it including a fuse.
Now you need to find the + signal wire that comes from the alternator - this is the one that turns off the red light on the dash.
You use the signal wire to turn on the solenoid and allow current to pass to the leisure battery, dont forget a fuse.
Make sure that all the wires are properly secured and extra insulation is put on the wire where any rubbing is likely to occur.
Now you can hook up the battery wires.
The leisure battery needs and earth to the vehicle body.
 
Hi Furyash,

I replaced both batteries with 85ah standard car battery so I can swap them if need and run TV of engine battery but we do have a split charger.

Richard
 
I have this one Power Integrator and can recommend it if your budget allows.
Just increase the wire thickness, I am sure it works with what they recommend but it will only improve with thicker wire.
It has an inbuild solar charge controller so adding a solar panel (or two!) later will be an easy job and money saved and less wiring hassle
 
My opinion would be, get 2 x 110amph batteries as a minimum and 2 x 80w solar panels for a start. The biggest energy saving that I have made is change all habitation bulbs for LED items. However, your cool box running off the batteries will kill them very quickly and the fan on the heating system is also a big draw item. LED's on everthing is the way to go.
 
Iveco Turbo Daily owner, self build

Hi Furyash, where about in Scotland are you?

If you're near enough you could bring your van round and I'll help you with your electictrickery. I have Edna, a Turbo Daily 35/10 LWB and run my "leisure battery" (actually another 110Ah van battery) from a split charger relay. It's really quite straightforward when you actually look at what's happening.

Mind, I'm heading off tomorrow for the sunny climes of Loch Duich and Loch Carron on a week long Dive Guide job, but shall be back to NE Fife next Sunday (ish).

DT
 
Dive Tramp said:
Hi Furyash, where about in Scotland are you?

If you're near enough you could bring your van round and I'll help you with your electictrickery. I have Edna, a Turbo Daily 35/10 LWB and run my "leisure battery" (actually another 110Ah van battery) from a split charger relay. It's really quite straightforward when you actually look at what's happening.

Mind, I'm heading off tomorrow for the sunny climes of Loch Duich and Loch Carron on a week long Dive Guide job, but shall be back to NE Fife next Sunday (ish).

DT
Click to expand...

Hi, thanks a lot for your offer, but unfortunately I'm a bit too far away, Near Rothiemay, Huntly, Aberdeenshire. Thanks very much though, and enjoy your holiday :)

I have been looking at the set ups on the net and yes it is starting to make sense now...but I still have a few questions...

Is it possible to buy a live battery cable with an inline fuse built in, or do you have to cut and crimp a cable yourself? I have looked, but the only cable I can find with inline fuses is thin.

Stupid question but...both the van and leisure battery will need to be earthed yeah?

So the set up is this.... live cable (from van battery) - inline fuse - smartcom relay (or whichever make, and a cable from the smartcom straight to the fridge unit once I get one?) - leisure battery positive terminal - both the van and leisure battery earthed, and the power from the leisure battery (positive and negative) going to inline fuses and then on to the electrical components, correct?!?

The next thing, I have a unit in the van with switches which send the power through to the lights and heater (which then have their own independent lights), it also has a battery power gauge on it, I guess its like a zig unit. The unit has a badge which says SeaWorld, but I cant find a link anywhere to this and just keep finding pictures of Orcas! So I'm guessing that SeaWorld is just a model but I don't know the make, does anyone know this unit? Cheers

Anyway, Im sure that I will find more questions to ask! Thanks very much to you all for your help and suggestions:bow:

Ash
 
n brown said:
close !cable with inline fuse from van battery pos to relay,cable with another inline fuse from relay to leisure battery. cable with inline fuse from fridge output to fridge ,
the van battery is already earthed,ie the negative is connected to the battery,the leisure battery should be earthed in the same way ,if it's easier,connect it to the van battery negative Waterproof 30A 12V 24V Inline ATC Blade Fuse Holder 12AWG | eBay
Click to expand...

Nice one n brown. Would that cable be thick enough to join the battery - relay - battery? Thanks a lot.
 
as you will have gathered by now,there's 2 basic ways of using the smartcom...either on its own or as a switch to trigger a bigger relay. the latter method is best,but the former is cheaper and simpler. I have the former set up in my van and used 4mm cable ,same as on these inline fuses,and it works fine for me. mind you ,I move about a lot !
 
a split charge relay is just an electrically operated switch that allows the leisure battery to charge when the engine is running but separates it from the engine battery when parked so you will not run the engine battery flat. Now that has been the way of it for several years. 'The problem is that the regulator in the alternator sees a fully charged engine battery and reduces the charge hence leisure battery takes several hours to charge. As you say winter in Scotland and solar is almost a waste of time. So you are left with 3 options, a generator, a wind charger, or finally a sterling (or other make) alternator to battery charger. This is a device that increases output from the alternator to ensure the leisure battery remains charged.
Those three options are in order of of price assuming a cheap and nasty genny, if you plump for a kipor or Honda that could move to the dearest option.
Alt -Batt charger most efficient and quickest charge
Genny reliable but standard charge rate
Wind genny fairly reliable I would think in Scotland in the winter but low output though runs 24hrs as long as there is wind.
There is a forth option which is a charger powered by heat from a solid fuel stove, again low output and only as long as your fire is lit.
So there you go lots to think off, main thing is to reduce your power consumption, fit LED lights have some solar LED lights even in winter these work for a few hours a day, use gas for heating and cooking and a tiny TV if you must have one. Run the radio off of the leisure battery NOT the engine battery.
Good luck. Better answer is sod off to Spain for the winter, hee hee.
 
img012.jpganother thing is gas lights i use them almost all the time in winter . light heat and get rid of flies .also stop mozzies ,even scottish ones . mine came from an old caravan . had them 13 yrs now . put them in all the truck conversions i do.you should just make one out on right handside wall.
 
Spain for the winter...or better yet New Zealand, that what I thought I was going to do when I was younger, but life and reality hit! How simple is it to re-wire the radio off the leisure battery? No TV, in the van or at home! And the heater and cooker are gas, the heater does use some electric for the fan though. I am hoping to get my electric cool box rigged up to it, its small, 25l, Im hoping it wont use up too much juice?!

Gas lights, excellent idea!!! I lived in a caravan for a long time in Caithness (used to be a contractor - tree felling) and I used gas lights in there, why didn't I think of that!?!?!?! Cheers.

The other thing, I have an old ex-military Landy 90 (1986) which I use on our croft and in the winter as the roads around us don't get ploughed! I was thinking of taking the battery out of that and using it as the second battery in the van, until I can get (afford) a good leisure battery, Im pretty sure its a truck battery,, bloody thing is huge, that would do the job right?

Thanks again for all the help.
 
Hello again, just back from a campervaning trip to the Cairngorms with Zak (my collie), and while I was away my girlfriend ordered me this;

12 Volt 70 Amp split charge relay system. ALT/70A5PNSPLITCHG12V | eBay

Any thoughts on it? Im see its rated to 70amps, which is more then the Smartcom. As said before I'm going to be running the internal lights (4 in total), my radio (if I can figure out how to wire that to the leisure battery), a 12v socket (which will power a small electric cool box when the van is running), and in once its starts getting cold again a heatsource 1600 gas heater (the fan is electric, plus a tiny led on the display), so not much.

The battery I'm putting in from my landy is 110 or 120 (to act as the "leisure" battery), and the starter battery in the van is something like 70 or 80, should I switch the batterys around, or does it not matter?

Thanks again
 
With the kit you girlfriend has ordered there is no sign (in the listing) of a voltage sensing device(like a Smartcom) and it looks probable that you will have to identify a connection on the alternator itself which becomes live when the alternator starts generating. The later is a valid scheme but most people avoid it, which accounts for the popularity of the various "Smartcom" offerings.

The Smartcom voltage sensor itself has only a 30 relay - I think it might be an ordinary "automotive relay". That,s hardly big enough and it's common practice to connect the output of a Smartcom to a bigger relay which joins the batteries together - 100 amp is a good place to start.

I fitted an amp meter to my leisure battery and was surprised to see very high currents flowing at times. Especially when first starting the engine 30amp goes in immediately before the alternator control gets across things.
Another thing I've seen (and modified my split charge to avoid it) is to do with the fact that the voltage on a battery can remain high enough to keep the Voltage Sensitive Device triggered for a short time after stopping the engine. **If you restart in that time I used to see (depending on the relative state of the batteries) a 30amp discharge to the glow plugs and end stop current to the starter motor as the split charge relay was still closed. Heavy duty wiring and a decent relay is a must in my opinion.

** Edit..I should have said it wasn't a Smartcom. In theory all these "should" drop out immediately the starter turns as the voltage falls to around 9v I believe.

If your electrickery is not up to understanding all that goes on you might do better to get a system like that posted in #3 which has heavy cable, fuses and a good capacity relay. ( I have no personal knowledge of it though) Of course the system you ordered may be ok if you can connect it up OK. I hope it is not intended for that kit to be simply wired to an "ignition on" wire )

You will need to do a fair amount of rewiring to take advantage of the auxiliary battery. A fuse panel will be the minimum you need to install,with feeds to the things you want to work of the leisure battery only
 
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I wouldn't worry to much about using the van radio, just keep an eye on the van voltage by using something like this
LED Car Battery Electric Cigarette Lighter Voltmeter Voltage Meter Gauge Tester | eBay

and fit one of these Hotsell LED Display Panel Meter Mini Digital Voltmeter DC 0V To 30V Blue/Red WST | eBay for the lb voltage. Although you can leave these connected all the time the leds will last longer if they are unplugged/ switched off when the van is not in use.

Try to keep the lb battery voltage (state of charge) higher than 12.2 (about 50% full) to 12.4v (75%) to maximise battery life. The engine battery should stay above 12.4v. These voltage readings will be much more accurate if taken an hour or so after charging or discharging.

Aim for a battery bank above 200 ah. It will last more than twice as long as one half the size. Solar panels will run the van in the summer and keep the batteries maintained in the winter.

Don't panic.

Mr B.
 
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