Split Charge Relay kits - warning!

[Alan2016]

Thanks for taking the time to reply Geoff, much appreciated. I'll look at putting something in place.

[TheNewRooster]

Yes the danger is that an un-fused cable will be damaged and short to earth, where currents exceeding 200-500 Amps can be expected.
In one design, no names mentioned, there is only one fuse, on the basis that the Split Charge Relay is mounted very to the battery terminal, and the length of cable is sufficiently short that the danger of it being damaged is very low - however that ignores the point that the SCR is most likely to be operated at the point of a collision and the cable the other side of the relay is hence LIVE and un-fused from the second battery ..... the relay will quite happily handle several 100's of Amps before it melts, either way there will be the equivalent of a free flying arc welder (arc welders use currents of 50+ Amps) under your bonnet

LOL Geoff...no names mentioned, But I will say they are NOT my kits.

[Markas]

Excuse the thread revival!
I'm looking to fit the Rayne Automotive split charge relay kit to my 'new' Bongo. the van already has a battery tray in place and I'm planning to liberate a 110Ah leisure battery from a caravan we're in the process of selling, if it fits in the hole, that is!!
As far as I can tell from the images on their website the kit has an in-line fuse at the starter battery end of the cable that links both batteries via the VSR, but none at the leisure battery end. The fitting notes suggest that the fuse already fitted is rated at 100A. Do I understand from previous posts in this thread that for safety it should have an additional fused positive terminal fitted at the leisure battery? The cube fuses appear to be available in different ratings; which should I go for? 100A again?
Thanks in advance for any replies.
Mark

[g8dhe]

Yes that is one of the dangerous ones! No fuse for the LB so you have an incipient Arc welder under the bonnet in a small front end collision
Fuses protect the cable so should have a rating no more than what the cable can handle, but really never needs to be more than the maximum charging current 50Amps is plenty.

[Markas]

So is the Rayne kit safe if fitted using a 50A fuse at the leisure battery end or can someone recommend a safer, but equally straightforward to install, alternative?

[g8dhe]

Yes Fuses are needed at EACH battery, fit an additional fuse at the LB on the Raynes kit and its fine.

[Markas]

Yes Fuses are needed at EACH battery, fit an additional fuse at the LB on the Raynes kit and its fine.

Thank you for a clear and concise answer

[TheNewRooster]

Yes Fuses are needed at EACH battery, fit an additional fuse at the LB on the Raynes kit and its fine.

I would like to add, Also fit individual fuse on the loom for the circuit swap. Rayne automotive/Busboy, doesn't seem to understand that cables need to be fused as close to the battery as possible. This circuit loom runs from the LB, along the bulk head, through the bulk head then he advises they are mounted behind the end panel of the dash between the drivers door and dash.
There is some quite sharp metal in there and I have had one occasion where the wires shorted and melted the loom, luckily the terminal on the LB was loose and it got snatched off quickly.
The circuit swap loom I make is fused close to the LB poz, and at the correct fuse ratings for each circuit.

[JillArchie]

Apologies! But I've made the mistake of buying the Ranes kit as well... I'm looking at 50 amp fuses on eBay but not sure what to buy (and how it therefore attaches!) Could someone please advise...

[g8dhe]

You might want to read this thread on FB if your have an account, same kit more problems reported https://www.facebook.com/photo.php?fbid ... ater&ifg=1 If its not to late you might want to consider returning the kit and going for a better quality one.

[Winnie-bongo]

I would definitely return the raynes kit and get one from TheNewRooster above. The raynes kit that was professionally fitted in my Bongo had poorly crimped terminals that eventually came off when the insulation stopped holding it, this caused heat which melted the relay oh and both batteries died. Now if the batteries hasn't died I wouldn't have found the faulty raynes kit and would have had a burnt out Bongo.
As mentioned their bypass kit has about two metres of three wires together before the fuse! Fuses should be as close to the battery as possible for safety rather than two metres to melt and burn. Then you realise they have three wires to feed six circuits.
I contacted raynes who said the kit was out of warranty so I guess it's only expected to last 12 months.

[mitchelln]

I eventually found my VSR mounted under the driver seat wired into the alternator. Feeds to fridge etc were fused, but no fuse up to the LB. Pretty shocking. I fitted one sharpish!