DIY split charge

[rayf3262]

What would be the best amp cable to use? I was thinking about 30?

1) what is the max current the cable is required to carry?
2) what is the length of the cable?
3) what is the acceptable voltage drop at maximum current?
4) what is the mean temperature of the cable?

With the answers to these questions you can calculate the correct size (CSA) of the cable you require.

Note, it will be helpful if you think of this piece of cable as a resistor.

 

[kitchenman]

Ryan, if you are fitting the battery to a car like mine there is a good place over the n/s front wheel under the bonnet. I have pictures
You would need a hell of a thick cable to go all the way to the back,
dave

 

[bry]

I've used something like one of these in the past. Much simpler and better in my opinon.

http://www.ebay.co.uk/itm/HIACE-SEL...ervan_Caravan_Accessories&hash=item2a2e062217

Good link mate,cheers:thumbs

 

[Barrbeast]

One of the reasons I'll be fitting a split charge to my Troll is because I want to fit a winch at some point, am I right in thinking that the relay will need to be a bit beefier than the one in the eBay link, ie. rated higher than 40A, like a T-Max or X-Charge system? :nenau

Should I be looking for slightly higher than the rating of the alternator (iirc 90A) minimum? I'm guessing a winch will likely draw more out the aux battery than that if it's working but surely the most that will go through the relay will be the max output of the alternator?

 

[Fez_uk]

I'd personally go for the bigger relay type. Winch can draw like 300amps depending on speed and weight it's pulling.

Winch will draw as much it can from the alternator then seek the rest of the amps from the batteries.

But I know plenty of people who run just one bigish battery for winching without issue, Unless your doing winch challenge stuff a 2nd battery with splitcharge is not really needed.

So a lesser amp relay won't be too bad on a overland style vehicle where the 2nd battery is more for running stuff when the engine is off.

 

[Banshee]

Probably going off topic a bit and probably a very crude question but how do I incorporate a relay into electrical wiring I'm adding to the car?

How do I know which one I need and how would I wire it in the example of say Spotlights

 

[96terrano]

Well, zenka and bought a split charge kit for the Hyundai, was £10, a nice maypole system, I only had £8:augie

Banshee, you want this diagram, :thumb2 simple 4 pin relay used for almost any simple circuit, pin 86 goes through a switch and then to the +ve feet to the relay, pin 30 will go to you're spotlights, this is daigram for a fuel pump, but just the same to wire up anything with a relay:thumb2

I'm running 4x 552 roof lights on mine and use a 30 amp relay....more than enough

 

[96terrano]

 

[96terrano]

bigger pic so you can see details

 

[Barrbeast]

Can't see Ryan's pic (work email doesn't always like posted images) so he may have done something similar, but assuming the switch for the lighting is going to be inside the truck I would take the live feed for it from one of the ignition wires that way the switch will only be live with the ignition on.

That's what I did with the manual pre-heat for my old Shogun (the glowplug ecu has a habit of going fizz and is £££ to replace). Switch was connected to the glowpug relay which had the added bonus that the switch wasn't being overloaded by the draw from the glowplugs (previous owner had just ran a wire direct from the +ve side of the battery to the busbar... I only discovered this on a very cold morning when the switch got hot, melted and burnt my finger !)

 

[Barrbeast]

... and now the work internet decides to show the picture and I see it's a pic of the split charge system Ryan bought rather than the relay set up for lighting, damn technology! :doh

 

[Barrbeast]

I'd personally go for the bigger relay type. Winch can draw like 300amps depending on speed and weight it's pulling.

Winch will draw as much it can from the alternator then seek the rest of the amps from the batteries.

But I know plenty of people who run just one bigish battery for winching without issue, Unless your doing winch challenge stuff a 2nd battery with splitcharge is not really needed.

So a lesser amp relay won't be too bad on a overland style vehicle where the 2nd battery is more for running stuff when the engine is off.

Cheers bud :thumbs So if I get this right my choices are:-

A) Another full size battery with on a split charge with a beefy relay to take the max draw from the alternator. Winch is connected to second battery.

-or-

B) Swap the Troll's main battery for a slightly larger one and use the old one (or a new normal sized battery) as the auxiliary one on a split charge to the larger battery via one of the smaller amp relays. Winch is connected to the main battery.

Think I'll go for go for A and leave my main battery doing it's normal thing with the auxiliary handling all the extras like the winch. Plus I like the extras on the T-Max like being able to link the batteries etc.

 

[96terrano]

Think I'll go for go for A and leave my main battery doing it's normal thing with the auxiliary handling all the extras like the winch. Plus I like the extras on the T-Max like being able to link the batteries etc.

think that's the best bet tbh, leave the original battery be:thumb2

 

[96terrano]

 

[solarman216]

View attachment 4249

What amps can it carry, does not look like many, Rick

 

[96terrano]

think the split charge unit i bought is for charging a caravan battery, as its got a fridge hookup too, will have to see if i can change it slightly for charging a on board battery, as the battery will be mounted under the boot floor, the instructions go on about 12 N and 12 S towing sockets:doh

 

[96terrano]

What amps can it carry, does not look like many, Rick

30 amps

 

[96terrano]

will be fitting a tow bar so might work alongside that

 

[Barrbeast]

think the split charge unit i bought is for charging a caravan battery, as its got a fridge hookup too, will have to see if i can change it slightly for charging a on board battery, as the battery will be mounted under the boot floor, the instructions go on about 12 N and 12 S towing sockets:doh

Yeh, reckon your right as 6, 4 & 2 (numbering on the relay) are the +ve pins on a 12 S socket.

 

[96terrano]

Yeh, reckon your right as 6, 4 & 2 (numbering on the relay) are the +ve pins on a 12 S socket.

In thinking of just connecting the outlet on the relay that's supposed to go to the 12s socket, straight to the leisure battery in the boot?, might work that way