Questions on Selecting Bus Bars

Hi, So the mods on our new truck camper have begun and my next order of business is to install my battery monitor.  I also will  later be installing my solar panels & inverter (2000w) pure sine wave) I will be purchasing.  Our TC has a basement area which as of right now looks like a good location to locate the charge controller and inverter when I get to it, as one of the walls divides the basement from the battery compartment.  I was hoping to make one positive & negative connection to the battery bank through the wall and to  positive & negative bus bars with the shunt connected between the battery bank and bus bars.  All my loads, positive and negative going to respective bus bars.  So on to my questions, first does this sound like a workable plan>  Second, when selecting bus bars, what are key details I should be looking for in bus bars?  Of course the required number of connections and wire size are factors.  I have seen so many different styles, configurations and of course brands so looking for any thoughts, ideas and input others may have. Thanks.

I'm not sure I understand the physical layout of your TC well, but I'd recommend mounting the shunt as close to the battery as possible. My shunt is bolted to a short steel strap that's attached directly to the battery's (-) terminal. All of my negative connections are routed to the other side of the shunt.

Your controller should be as close to the battery-bank as possible (looks like you've got that location identified) and use thick gauge wire from the controller to the battery-bank (I used 2 gauge wire.) Make sure you fuse the positive wire between the controller and (+) battery terminal with an appropriately rated fuse. That fuse should be right next the battery.

We have multiple panels, so we have a junction box on the roof where all the panels' pos & neg wires tie together. Our bus bars are in the junction box, and they have screw-in terminals that were big enough for the 8 gauge wires that run from the panels to the junction box. I ran 4 gauge wire from the junction box to the controller, but you probably won't need that thick of a wire gauge.

I hope that answers your questions. Ours is a pretty typical setup, and it works well, so I hope it helps you design yours.

Kev

My go to for buss bars is Blue Seas Systems.  They are tinned copper bars and they are rated very conservatively.  I have used many of them and have not had an issue with them.

Kevin Means said:

I'm not sure I understand the physical layout of your TC well, but I'd recommend mounting the shunt as close to the battery as possible. My shunt is bolted to a short steel strap that's attached directly to the battery's (-) terminal. All of my negative connections are routed to the other side of the shunt.

Your controller should be as close to the battery-bank as possible (looks like you've got that location identified) and use thick gauge wire from the controller to the battery-bank (I used 2 gauge wire.) Make sure you fuse the positive wire between the controller and (+) battery terminal with an appropriately rated fuse. That fuse should be right next the battery.

We have multiple panels, so we have a junction box on the roof where all the panels' pos & neg wires tie together. Our bus bars are in the junction box, and they have screw-in terminals that were big enough for the 8 gauge wires that run from the panels to the junction box. I ran 4 gauge wire from the junction box to the controller, but you probably won't need that thick of a wire gauge.

I hope that answers your questions. Ours is a pretty typical setup, and it works well, so I hope it helps you design yours.

Kev

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Thanks Kev. To answer your question on the physical layout, the wall of the basement storage area where I plan to install the shunt, charge controller & inverter also is one of the walls to the battery compartment, so in other words they are back to back which will require me to drill through the wall to route the wires to the battery, so approximately a 1-foot run of wire to make the connection. I have chosen this location for a few reasons, but the main reason is to get these components as close to the batteries as possible.  Your set-up approach is very similar to the one I used on my previous rig (TT) and actually better because in my truck camper it looks like I will be able to get these components much closer to the batteries than I was able on my TT.  What I am trying to understand is if my plan to make one positive & negative connection to the battery bank on that end and on the other side of the battery compartment wall in the proposed basement storage area next to the components, mount a positive and negative bus bar to attach all my loads to, rather than doing so in the battery compartment.

boatbuilder said:

My go to for buss bars is Blue Seas Systems.  They are tinned copper bars and they are rated very conservatively.  I have used many of them and have not had an issue with them.

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Thank you for this, I am familiar with their products from my sailing days many moos ago, never thought about it for my TC application but worth checking into. Thanks.

boatbuilder said:

My go to for buss bars is Blue Seas Systems.  They are tinned copper bars and they are rated very conservatively.  I have used many of them and have not had an issue with them.

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Thanks again Charlie for the suggestion, on a product you reminded me of from my boating day's.  I did end up buying the Blue Sea Systems bus bars and installed them this past weekend as part of my battery monitor and future solar & inverter installs.  As in the past, so far very happy with the quality of their product.  I ended up installing the shunt and a catastrophic fuse in the battery box where I made the battery monitor connections and routed the positive & negative cables to the bus bars on the inner wall, adjoining the battery box.  Now when I proceed with the next stages of mods all the difficult access work is complete and will make the future connections a breeze.

I tend to agree Blue Sea makes some good products, and are generally a safe bet.  There is no one right answer here, bus bars should be used sparingly, they are not a replacement for fuse boxes, connections should always be fused correctly for the size of the smallest downstream wire.    Now in my motorhome, I have an electrical bay on the drivers side and battery back opposite under the steps on the passenger side.  Therefore I have installed a positive bus bar with 4 large studs in the electrical bay that then connects over the the battery with a thick positive cable and is protected by a large (400 amp?) breaker.  All of the high amp accessories in the electrical bay connect to this bar (inverter, charger, solar charge controller, etc.)  Any low draw items I might add would be connected to a fuse block which would then be connected to the bus bar.  Of course on grounds they can all be ran to a common grounding bar / block so can have both large and small connection points.

Isaac-1 said:

I tend to agree Blue Sea makes some good products, and are generally a safe bet.  There is no one right answer here, bus bars should be used sparingly, they are not a replacement for fuse boxes, connections should always be fused correctly for the size of the smallest downstream wire.    Now in my motorhome, I have an electrical bay on the drivers side and battery back opposite under the steps on the passenger side.  Therefore I have installed a positive bus bar with 4 large studs in the electrical bay that then connects over the the battery with a thick positive cable and is protected by a large (400 amp?) breaker.  All of the high amp accessories in the electrical bay connect to this bar (inverter, charger, solar charge controller, etc.)  Any low draw items I might add would be connected to a fuse block which would then be connected to the bus bar.  Of course on grounds they can all be ran to a common grounding bar / block so can have both large and small connection points.

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I installed the bus bars not as a replacement for fuses, rather as a convenient means to connect loads without doing it all at the battery.  In my battery box I installed a catastrophic fuse holder with a 200A T9 fuse, I have the option of replacing the fuse with a higher amp fuse if future needs dictate.  But it is a good point you make on fusing, because it boggles the mind how many installs are done without adequate if any fusing at all.

I wholeheartedly agree with minimizing connections at the batteries themselves. That was one of the biggest things I saw when working on the service side of boats was customers dewinterizing their own boats and missing a cable.  The head electrical engineer at Cruisers and Rampage was a fanatic that each battery should only have one positive cable and one negative cable.  We strictly followed ABYC guidelines for cable sizing and over current protection.