hi was wondering if anyone could help me with what i would need and how to go about setting up dual battery system with split charging for my series and what would i need. Also was wondering how you could isolate individual batteries i.e starting battery when engine off.
Series 3 Split Charge System
- Thread starter luke1838
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dr pepper
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Messing with boats I've come accross this a lot.
You can do it with a simple relay, tho it has to be a heavy duty one.
Connect the contacts of the relay so that when its energised it connects the 2 batteries together, then connect one side of the relay coil to earth, and connect the other side of the coil to the alty warning light terminal, when the alty starts charging the relay will close and connect both batteries together, the only drawback with this is that if the engine battery is fully charged and the other battery fully flat, when the relay closes there will be a big inrush current into the discharged battery, that said you come accross the same circuits in boats and caravans a lot.
When you start the engine you have to just blip the throttle once to make the charge light go out, as the alty has to energise the relay.
Theres plent of info on the net how to connect it all up, google 'split charge circuit'.
If you want to spend money, stirling do a proper split charge controller electronic module, which charges and conditions both batteries.
You can do it with a simple relay, tho it has to be a heavy duty one.
Connect the contacts of the relay so that when its energised it connects the 2 batteries together, then connect one side of the relay coil to earth, and connect the other side of the coil to the alty warning light terminal, when the alty starts charging the relay will close and connect both batteries together, the only drawback with this is that if the engine battery is fully charged and the other battery fully flat, when the relay closes there will be a big inrush current into the discharged battery, that said you come accross the same circuits in boats and caravans a lot.
When you start the engine you have to just blip the throttle once to make the charge light go out, as the alty has to energise the relay.
Theres plent of info on the net how to connect it all up, google 'split charge circuit'.
If you want to spend money, stirling do a proper split charge controller electronic module, which charges and conditions both batteries.
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why dont you read the method described in the Q's and A's section?
wots the point of having a technical FAQ section if peeps are to lazy to look?
wots the point of having a technical FAQ section if peeps are to lazy to look?
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Not heard of anyone doing it on a Series, but, popular with Disco people is to put a second alternator on so you have completely separate systems... Seems a cunning plan... though not required
Newbie with a 79 88 inch series 3 half way through restoration. Fitted two optima red batteries and a split charge relay system. I get input to the relay when car is running but no output to second battery. I recently resided the vehicle with after Market harnesses and guess I have messed up somewhere.... :0)
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look at the wiring in the FAQ section
ford369
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if you buy a lucas split charge relay it comes with all the wiring details
borristherat
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just to put a spanner in the works. for winches, split charge systems ect that need quite a big relay i have a cheat if it helps. big relays are big bucks but standard 40amp car relays (the black cube ones about 20x20x20mm) are very cheap (£2) so what i do is run multiple relays in parallel, each with its own 30amp blade fuse. standard relays/fuses and lots cheaper than a shop bought "kit".
i am sure most of you will be able to make your own but if anybody wants more info on how i did my split charge and winch wiring using these relays let me know and i can give you enough info to copy my method.
i am sure most of you will be able to make your own but if anybody wants more info on how i did my split charge and winch wiring using these relays let me know and i can give you enough info to copy my method.
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£10.00 for a 200 amp split charger relay is not exactly big money. It's not £2 a relay, but, as your talking about using multiple relays i'd bet that a 200amp relay for £10.00 works out cheaper + is a proper job.
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Okay - at the risk of sounding like i'm dumb and a newbie. Where the frik is the FAQ....
http://www.landyzone.co.uk/lz/f38/wiring-split-charge-relay-system-61268.html
borristherat
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you cant find a decent 200 amp cont relay for £12, a s**t one is £12.50 + £1.50 postage, a half decent one is £50 and a good one is more like £100.
and how is multiple smaller relays in parallel not "a proper job" you also have the advantage of a still usable system if a part of it developes a fault.
each to thier own you do it your way i will do it mine. the split charge and winch system have been on my other 4x4 10 years and still work. i dont think you will find your chinese £12.50 relay lasts that long, buy chinese buy thrice.
won't you just get very quick cascade failure when one of the relays fails as the others will be over loaded ? - i hope you carry a fire extinguisher with you
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not if yu build in redundancy
so instead of one proper relay say we fit 10 pound shop ones, the redundant system being a mirror - so 20 relays, that's a lot of wiring
is this so form of very very very subtle spam Mr MHM ?
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not in the slightest, Sean - I was thinking that instead of 3 40A ones, yu could fit 4, so if one fails, yu still have the necessary 3 - ie 120A rated - more than enough for Alternator charging.
Or have I got the wrong end of the stick? I aint suggesting it - just saying it is a reasonable alternative.
sounds a lot of hassle, unless you are on a tight budget or can get relays and the wiring cheap - keep it simple etc
borristherat
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25 amp fuse on first relay that also powers the primery 30 amp on all the others = 25 amp fuse fails only if you have a fault. also you can make whatever size circuit you want in multiples of 30 amps + you can build in redundancy or even 2 primeries if you like.
why would you want a 200amp system on a 35amp land rover anyhow.
its only an option to save a few quid, while using easy to obtain and replace components.
your not chinese are you? i didnt meen to offend you by mentioning your engineering is sh*t...............me, i buy british i do.
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