Connecting leisure battery to fuse box terminal?

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dontknowz
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Connecting leisure battery to fuse box terminal?

Post by dontknowz »

Hi just wanted to double check if im ok connecting the positive 12v cable to the free 40 amp connector on the fuse box? I’ll attach a picture so you know what Im on about but i want it as neat as possible and don’t really want it on the battery connections. Im running 40 amp inline fuses and atm im connecting it directly to a 12v kill switch and then into a fuse box to power the lights and usb ports for now and I’ll eventually put a smart charger and leisure battery in once i have the funds

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Re: Connecting leisure battery to fuse box terminal?

Post by Doc »

So long as the wire you are using is rated for 40A or higher, there shouldn't be an issue.
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Re: Connecting leisure battery to fuse box terminal?

Post by Revtnr »

You should use split charge relay so will not drain the crank battery.


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Nicklouse
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Re: Connecting leisure battery to fuse box terminal?

Post by Nicklouse »

I would not.

I would have it connected directly to the main battery with suitable sized cable and fuses.

Why, if you have been using the leisure battery and put it a state of low charge there is the potential for a large current to be drawn by it at the start of charging from the alternator.

Not saying that it is wrong but I would be expecting blown fuses or blown fusible links.

I use 100amp fuses and a 120amp voltage sensing relay along with cable rated to 110amp. My alternator is rated at 140amp.
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dontknowz
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Re: Connecting leisure battery to fuse box terminal?

Post by dontknowz »

Nicklouse wrote:I would not.

I would have it connected directly to the main battery with suitable sized cable and fuses.

Why, if you have been using the leisure battery and put it a state of low charge there is the potential for a large current to be drawn by it at the start of charging from the alternator.

Not saying that it is wrong but I would be expecting blown fuses or blown fusible links.

I use 100amp fuses and a 120amp voltage sensing relay along with cable rated to 110amp. My alternator is rated at 140amp.
Hi so atm I’m not running a leisure battery and the cable is connected to a kill switch and then plugged straight into a 12v fuse box but the cable i have is 110A and i have 40A inline fuses for the time being I’m going to get a smart charger victron 30a non isolated so I’m thinking with that in place you can set what rates it charges the leisure battery and with it only being a max of 30a the 40a fuses will be fine? Im still doing research into it so not 100% would you say with all that in-place id be safe to use it or just stick with it on the battery?


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Re: Connecting leisure battery to fuse box terminal?

Post by Jenk0 »

Hi i have 2 x 200AH lithium batteries fitted in the rear of mine. I connected cable directly to alternator output routed to follow existing charge cable but in length of trunking then through a mega fuse with a 60A fuse. Then up to a 50amp DC-DC charger. Works great and will deliver maximum charge to the leisure battery without detriment to your cranking battery and is much safer than a split charger. (Which was my original installation) and works well with smart alternators if you have a newer van. It will also charge your cranking battery if you are connected to a solar charger. Hope this helps.
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Re: Connecting leisure battery to fuse box terminal?

Post by spgrace »

Jenk0 wrote: Thu Nov 23, 2023 8:49 pm Hi i have 2 x 200AH lithium batteries fitted in the rear of mine. I connected cable directly to alternator output routed to follow existing charge cable but in length of trunking then through a mega fuse with a 60A fuse. Then up to a 50amp DC-DC charger. Works great and will deliver maximum charge to the leisure battery without detriment to your cranking battery and is much safer than a split charger. (Which was my original installation) and works well with smart alternators if you have a newer van. It will also charge your cranking battery if you are connected to a solar charger. Hope this helps.
When you say you connected directly to the alternator output do you have any more details?

I am good with all the other wiring for my DC to DC setup but not clear if I should go to fuse box, battery or alternator . . !
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dontknowz
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Re: Connecting leisure battery to fuse box terminal?

Post by dontknowz »

spgrace wrote: When you say you connected directly to the alternator output do you have any more details?

I am good with all the other wiring for my DC to DC setup but not clear if I should go to fuse box, battery or alternator . . !
Id go from the fuse box or battery its alot easier thats what I’ve done I’ve gone from the battery but the picture i used for the fuse box connector would also work and look neater


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Re: Connecting leisure battery to fuse box terminal?

Post by spgrace »

Thanks, I will look at the bits needed to go from the fuse box. On the battery terminal, did you just connect to the clamp bolt or change the whole terminal.
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dontknowz
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Re: Connecting leisure battery to fuse box terminal?

Post by dontknowz »

spgrace wrote:Thanks, I will look at the bits needed to go from the fuse box. On the battery terminal, did you just connect to the clamp bolt or change the whole terminal.
Ive just put it directly to the battery clamp bolt work fine wouldn’t say it looks the neatest but will be moving it to the fuse box, that fuse box terminal does have a rating on it so id double check if yours is a smart alternator or not and what amperage you can expect.


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Re: Connecting leisure battery to fuse box terminal?

Post by spgrace »

Will do, planning on 18A Victron DC to DC charger right now so it should work perfect. Thank you for the guidance.
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