My comedy electrics

[rjj1]

Greetings. My first post here.

Had the Bongo coming up to 2 years now. A mid conversion from Manchester Campers with electrics I, and a recently employed auto-electrician don't understand:

Leisure battery under the bonnet with a split charger.
Rear courtesy lights and stereo wired to leisure battery.
Also has 3 12v halogen spots which work of the electric hook up only.
Compressor fridge which works off the leisure battery or mains hook up.

Fridge left on => dead battery, courtesy lights and stereo stop working.
Remove dead battery to charge - stereo works again, but only after engine running for about 5 mins and courtesy lights work but only with the engine running (not much use!)

As there is no control panel or read out, I never have any idea how much charge is in the leisure battery. I'm wondering if letting it run to completely empty may have knackered it even after a full mains charge it only lasts about a week, although Boris is only doing very short runs most of the time now.

So the leisure battery is out for now. At least the stereo works. No courtesy lights which will become a pain when the days start to shorten and of course I have to put it back in to camp and use the fridge.

Finally, surely those 12v halogen spots would run of the leisure battery?

So should I try a new battery? Is it worth having the stereo and courtesy lights rewired to run off the vehicle battery, we're not going to be camping for hours with the stereo and rear courtesy lights on anyway? And is there any point in putting one of those small solar chargers in the front window and hooking it up to the leisure battery?

Bit of a ramble I know, sorry.

Thanks and pleased to meet you all having been reading the forums for months without posting!

[dave_aber]

Layout sounds (sort of) logical to me.

Presumably, when you say "halogen spots" you mean ones inside the rear of the van for general illumination, not "Paddy Hopkirk" style on the front bumper?

Sounds to me like, possibly, a duff L/B. Once you remove it, and run the engine you say that after about 5 mins the radio and courtesy lights work again - I suspect that this is when the S/B (also maybe a bit duff) has got up to charge and the split-charge system is closing and thus powering up the L/B connection. You have insulated the L/B "+" terminal, right?

On a decent L/B, you should be able to leave the fridge on for 3-4 days if it's a compressor one. I can get 4 days out of a 110aH L/B running a Vitrifrigo C42L fridge, and a few lights / phone charger / etc.

As for the charge level, it's fairly simple to wire in a wee rectangular LED voltmeter (eBay) with a change-over switch to either battery so you can monitor each of them. They fit OK in the dash if you pull out a few un-used switch blanks.

Any garage can test a battery for you using the "Dr Frankenstein" load tester.

HTH

Dave

[missfixit70]

If you've run the leisure battery right down on more than one occasion, you'll have shortened it's life. A battery only has so many "cycles" in it anyway, so it sounds like it's had it's day to me.
May be worth swapping the halogen spot bulbs for led ones that draw less power aswell.

[rjj1]

Thanks for the quick reply. I followed most of it, but I'm not well up on electrics.
What do you mean by: you have insulated the L/B "+" terminal?

I agree the L/B may be duff now. Does a complete discharge damage them?

I'd be interested in wired in voltmeters and will look into this.

So do you think replacing the L/B is the first thing to try?

[missfixit70]

This is one of many threads that should help with the voltmeter - http://www.igmaynard.co.uk/bongo/forum/ ... =voltmeter

I'd say a new LB is the way to go from what you've said, what size battery have you got ATM? The biggest possible is @110ah depending on the type of battery tray.

Don't sling the old one out, I just weighed in my old one as scrap for £7

[nigelgibson]

It is possible to wire all sorts of combinations up and there are lots of combinations of 12/240, SB/LB so don't be concerned.

i'm a total amateur on auto leccy but found the sealey power probe recommended by 321away [see below] to be a great addition to the tool kit.

http://www.ebay.co.uk/itm/SEALEY-PP1-AU ... 20ba46f924

[dave_aber]

What I mean is, if you remove the L/B, the + terminal is dead for as long as the split-charge system isn't trying to charge that battery.

Once you start the engine, the split charge relay will close, and the L/B "+" terminal which is flapping around on the end of the wire will become live (12v). If it shorts out, you will in the best case blow one of the 2 fuses in the power line from S/B, via relay, to L/B. In the worst case, the split-charging system won't have fuses in the line and you will have something more serious - either a burnt out relay or burnt out wiring - or worse......

You ideally will have a, let's say, 50A fuse at either end, 60A cable and a 70A relay.

[Jaws]

Welcome to the forum!

Somebody here will help to sort it all out but be prepared for some more questions. For example:

Is there some sort of Power Management Unit fitted? If the 12v 'spots' only work on hook up there must be at least a transformer?

Certainly possible that your LB is duff but if everything has been OK up to now it suggests something has failed e.g. split charge relay. Worth having both batteries checked but beware fitting new ones unless you are happy they are being properly charged!

Wow. Just seen all the other replies! Point made.

[rjj1]

Thanks all,

but no, the positive connection for the L/B has not been insulated. I see now this is dangerous. I know the split charger has a fuse and is working (checked by auto electrician recently).

How do I insulate the positive end. Can I just wrap gaffer tape round it or is it more serious than that?

[dave_aber]

Personally, I wouldn't want the terminal to be all sticky once I'd de-insulated it.

Stick it in a poly bag - a thick one, not a tesco bag. Make sure it can't chafe on anything, and use a wee bit of tape to hold it on.

Alternatively, if the lead is properly fused, i.e. a fuse very close to the L/B terminal, then just pull that fuse out.

[Dabs]

Hi RJ

My ex Bongo was a Manchester Campers converted one (rear galley) it would still have the same set up as yours in split charge etc I too had similar problem which after having the leisure battery tested proved to be a dead cell (after @3 years of use) a new leisure battery sorted mine.In regard to the halogen lights I would think they could be rewired to run from leisure battery,main downside I found to them was that running from 240v they got incredibly hot (I burnt my follically challenged head regularly!! ouch!!).If they bother you may be better to have them changed to led ones (low usage and cool to touch!).

Good luck with a fix im sure it isnt serious!!

Dabs