L/Battery - go large or go lithium?
- Thread starter Chris1983
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- dc - dc charger victron vsr
Every earth/negative/ground/-Ve (all the same thing) goes to one side of the shunt and a single fat negative cable goes from the other side of the shunt to the negative post of the leisure battery.
Any negatives can go to the bodywork of the vehicle if it helps reduce the amount of cables in a negative busbar as long as at least one fat earth from this negative busbar connects to the bodywork and shunt too to effectively connect these waifs and strays to the shunt load side.
The point with the shunt is that everything electrically connected to the leisure battery has to go through the shunt sampler via the leisure battery negative post so that the shunt can tell you what's in the battery at any point in the days activities eg solar bunging in power, engine running and bunging in power or on EHU and Victron IP 22 bunging in power.
Any negatives can go to the bodywork of the vehicle if it helps reduce the amount of cables in a negative busbar as long as at least one fat earth from this negative busbar connects to the bodywork and shunt too to effectively connect these waifs and strays to the shunt load side.
The point with the shunt is that everything electrically connected to the leisure battery has to go through the shunt sampler via the leisure battery negative post so that the shunt can tell you what's in the battery at any point in the days activities eg solar bunging in power, engine running and bunging in power or on EHU and Victron IP 22 bunging in power.
So I think i get that?
But what about the circles yellow wires here?
And the green circled fat negative to seat base stays between -ve lb post and chassis?
This is I think how it looks now.
Questions if I may.
1-do I need to do anything with grey/ brown that exit small fuse box in centre and disappear under floor? Re: shunt
2-am i grounding negative bus bar OR battery to chassis?
Does the dreadful attempt at diagram look okay otherwise
This bit
The ONLY thing that should be connected to the LB negative terminal is the battery minus side of the shunt.
Everything else connects to the system minus side of the shunt. It doesn't really matter how these are connected, but to keep things simple:
Connect the (system minus terminal) shunt to the busbar
Connect the chassis ground to the busbar
Connect any other negative to the busbar
That way, the busbar is being used as intended, as a single point of connection for every single negative. If all your negatives including a chassis ground for any going via that route, everything is then going through the shunt.
The ONLY thing that should be connected to the LB negative terminal is the battery minus side of the shunt.
Everything else connects to the system minus side of the shunt. It doesn't really matter how these are connected, but to keep things simple:
Connect the (system minus terminal) shunt to the busbar
Connect the chassis ground to the busbar
Connect any other negative to the busbar
That way, the busbar is being used as intended, as a single point of connection for every single negative. If all your negatives including a chassis ground for any going via that route, everything is then going through the shunt.
I'm not seeing those wires on any of your pictures, are they just connected to the small fuse holder in your panel?
This is like explaining to my Dad that he needs to retune his FreeSat box every now and then rather than him going off on a tangent about the government removing the free TV licence and trying to force him to pay by gradually removing his favourite channels... 'kin maniac, in the end we go around there retune his box and he goes on to worry about AI deleting him... scatter gun logic and the dark arts are obviously easier to grasp.
Anyway back on course and as @TallPaul_S reiterated above only fat negative connected to the leisure battery should be from the "to leisure battery" side of the shunt sampler, this cable needs to be as fat as the single red coming from the positive post and going through your 100A isolator as these cables between them carry any potential maximum current that your leisure battery needs to satisfy your habitation load.
I run a 2kw inverter so the two individual fat cables, positive and negative, connected to my leisure battery are "0" guage, the black goes about 300mm to the shunt and the positive goes the same distance but through a 250A fuse to one side of the battery isolator and then onwards from the isolator to the cluster of various sized fuses located under the seat too.
Anyway back on course and as @TallPaul_S reiterated above only fat negative connected to the leisure battery should be from the "to leisure battery" side of the shunt sampler, this cable needs to be as fat as the single red coming from the positive post and going through your 100A isolator as these cables between them carry any potential maximum current that your leisure battery needs to satisfy your habitation load.
I run a 2kw inverter so the two individual fat cables, positive and negative, connected to my leisure battery are "0" guage, the black goes about 300mm to the shunt and the positive goes the same distance but through a 250A fuse to one side of the battery isolator and then onwards from the isolator to the cluster of various sized fuses located under the seat too.
Centre of seat cloud shape, has wires going into or coming out of seat floor.
One leaves red 40 fuse.
Three connected to three fuse box one brown two grey. Small gauge.
If you're connected to the fuse box they they'll be positive connections so don't worry about them.
Tbh, even if they were negative connections, so long as they go back to a ground point (chassis ground), because you're also connecting your negative busbar to chassis ground, that connects every other chassis ground in your van to the busbar.
Same as mine pretty much, 300a MRBF on the positive terminal via a chunky copper busbar, 50mm² cable to a 300a isolator switch, then to my fused busbar (250a mega for the 2000w inverter + midi fuses for DC-DC, MPPT, fuse boxes etc). Then the same 50mm² on my negative side via the shunt, busbar, and 50mm² to my 2000w inverter.
But seriously, AI
argh numbers argh AI!! Arghhhh
But seriously all, very many thanks for patience
It's a shame/blessing (delete as appropriate) 
that you're so far North as a lot of this becomes more obvious with someone else pointing and shouting, I find it easier to pick things up this way anyway.
Van leisure electrics are a bit weird though as even though they do come under the IEE regs the emphasis on diversity, not that sort, is more usually external to the van with earth leakage and over current protection down to the site operator and you never see earth stakes in use with campers as you would say when the Circus or funfair comes to town using bigarsed generators.
Regarding bona fide van converters the leisure electrics never stand up to too much scrutiny either with the fittings being non domestic and somewhere between toy shop and fit for purpose.
that you're so far North as a lot of this becomes more obvious with someone else pointing and shouting, I find it easier to pick things up this way anyway.Van leisure electrics are a bit weird though as even though they do come under the IEE regs the emphasis on diversity, not that sort, is more usually external to the van with earth leakage and over current protection down to the site operator and you never see earth stakes in use with campers as you would say when the Circus or funfair comes to town using bigarsed generators.
Regarding bona fide van converters the leisure electrics never stand up to too much scrutiny either with the fittings being non domestic and somewhere between toy shop and fit for purpose.
Hopefully the only fire you see today!!
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