Which split charge system? Which battery?

I got the national luna from south africa for about 80 quid

Its a time delayed relay system with a nice display - its a good system but I wouln't pay 170 quid for it

Have a look at electrical wiring products they have a boat switch which can be used and you can choose either battery

But whats wrong with the relay system for a few quid from a caavan shop

The others are pretty much as good and I believe they have 2 year warrenties on them compared to optimas

Rich

Did you buy off the national luna website or ring them up in SA? What about customs / taxes etc etc? Is it just a case of giving them your visa details and waiting for the courier man? I like the sound of buying direct and saving cash!

Tucked it under my arm and wandered thru airport security with a box of electronics and wires, didn't get stoppped until switzerland who still let me through with it.

Try the safari centre in cape town as they have shipped stuff direct to the UK (including roof tents !)

Rich

You could do what I've done - get the 40A relay and feed the coil on it from the sensor wire on the alternator - the relay will only activate under the same conditions as the charge warning light going out.

Seems to work pretty well really.

P.

I'm sure Halfords sell a split charge kit.....not very expensive either.

Yes.

Exide are made by Optima and are just as good IMO. I will probably replace my 3 Yellow Top Optimas with tham when they die (I've had a good 4+ years from them - with some rather serious abuse, and they show no sign of losing their charge or reliability yet, though).

Ask them to send it plain wrapped, marked as a gift then send the receipt by letter. You could then try to avoid the duty/tax.

I did not say this, by the way, and have no knowledge of the person currently using my 'puter... honest...

ang on a mo, there's a knock at the door, coupla suited blokes...

Won't be a mo...

erm...

Friend has the same system to charge the batteries for lighting and water pumping on his narrow boat. Seems to work fine.

Richard

Try Towsure (caravan camping specialist) in Sheffield or a local motor factors. My local Romac store does a caravan split charging system for less than £25 if I remember rightly.

Stew.

Found this website whilst looking for something else.

This should take you straight to the split charger page

Nigel

Then I got bored and googled some and found:

Lead Acid Battery Split Charge Module for £7.99 from

Nigel

Funny, I looked at this yesterday in the maplin catalogue whilst I was supoposed to be designing some briudge foundations (funny how landy's take over your life!).

Anyway, the description in the catalogue reads: "bla bla bla... The charging current is distributed in such a manner that a discharged battery is charged more intensively than a battery which is almost charged. ...bla bla bla"

As I understand it the split charge system should "ideally" charge only the starter battrery and then drop over to the leisure battery when the voltage of the starter battery is at 13.2V. The maplin systems would seem to charge both at once but at different intensities? Also, I wonder how much power this system uses to run?

Has anyone got one of these installed and could comment on it?

J>Then I got bored and googled some and found:

I've just bought one of these as I intend to fit a second battery to my 110 at some point. Just recently one of these modules went for £25 on ebay and there is another one up at the moment, people just don't check prices out before they buy do they.

Now I've got the module and have had a chance to check it out I suspect it may be just two schottky diodes potted in a plastic box with attached wires. It certainly measures that way with voltage drop of under 0.1V between the

• in and each of the alternator outs. Not sure how much schotkkys cost but it may be cheaper to just buy the diodes ad make it.

Sounds more like a little relay to me !

Steve

Hi Jon,

I get the imprestion you are not into electrics, you don't need to go for the expencive type, just use a 40A relay and that will cost you about £2 ish, if you send me a email I will send you a attatchment of a circuit of a split relay system. snipped-for-privacy@ntlworld.com

The theory about batterys, a battery will only charge if it requires it, ie if the battery is fully charged it take any current but if the battery is down it will take current, so the lower the state of the battery the more the current !so if both batterys are down they will both get a charge.

Hope that makes sense, but these people like to make money and it only requires the simple one !

Steve

Except you must limit the charging current, if the battery is demanding too much for its own good.

Steve

There is no need to limit the current, The alternater will limit that !

Steve

If you have an 85A alternator?

I use a 120A relay, seems fine - still only cost a couplaquid.

ISTR that schotkkys vary from about 1V downwards depending on the current and the model of diode itself. I was using a fluke 77 on the diode test setting. I'm a bit (very!) rusty on my electronics and was hoping to dig out my copy of the art of electronics at the weekend to refresh my mind but it didn't happen.