Question on Multiple 12V Battery Connections

[TucsonJim]

I have multiple connections I'm trying to make on my positive battery terminal. If I include the two connections the RV manufacturer made, the solar connections, inverter connections, and possibly others, the available real estate is getting very tight. I'd like to run one connection from the battery to something like a 12V buss line, but can't seem to find a 12V buss that can handle heavy gauge wire that is needed for some of these connections. Does anybody have a tidy solution?

Thanks,

Jim

[Jimf1234]

I like these 2-1/0 in and 4-4 gauge out. junction block

[free_radical]

RoyB wrote:


I would be careful however not to introduce different charging length paths from your charging source when feeding multiple batteries. You want each battey in your battery bank to use the same charging path lengths to insure each battery in the bank gets the same charging current when being charged. Otherwise some batteries will charge differently than the others which may result in poor performance and eventually do harm to the battery. This is very important for getting long life out of your battery bank.

Just some of my thoughts
Roy Ken

OP and others might find this helpful

http://www.smartgauge.co.uk/batt_con.html

[Gjac]

You guys are fancy, I just used a steel plate with two drilled holes one attaches to the battery post the other I insalled nut and bolt to attach extra cables from my inverter, and generator.

[Joe_Way]

Calkidd wrote:
That's a grounding bus bar. It will accept maybe 6 awg wire. We're talking 2 awg and bigger.

OK...maybe THIS. Or add THIS from the same grounding bar page. Either of these would add 2/0 connectivity to the ground bus bars.

[Calkidd]

That's a grounding bus bar. It will accept maybe 6 awg wire. We're talking 2 awg and bigger.

[Joe_Way]

Home Depot has a number of choices of bus bar at reasonable prices...search their website for grounding bars.

This one is $7.83 with free shipping to store...

Moderator edit to re-size picture to forum recommended limit of 640px maximum width.

[Calkidd]

westend wrote:

Now this I like. I may use the plain junction box like I did for my combiner on my roof.

Sure thing, just make sure the lug bar can handle the amperage.

For sure. I would use the crushed copper tubing and drill a few holes.

[Veebyes]

All kinds of goodies can be found at a marine supplier like defender.com or westmarine.com Defender likely to have more at better prices.

[westend]

Now this I like. I may use the plain junction box like I did for my combiner on my roof.

Sure thing, just make sure the lug bar can handle the amperage.

[Harvey51]

Wow, nice setups! I have a very low current setup and just used breaker box ground connectors that I happened to have. Like this - unfortunately high priced but mine were spares from a new sub box I had.
http://www.amazon.com/Eaton-Corporation-Ground-Bar-Gbk14P/dp/B00S0WYDJ4/ref=sr_1_7?s=hi&ie=UTF8&qid=1462577468&sr=1-7&keywords=breaker+box+ground+connector

[Calkidd]

westend wrote:
I made three of these bus boxes. In this picture you can see three device leads and their individual fuses. It is a 4" outdoor junction box with two pieces of HDPE used as standoffs for the copper bar. I had everything on hand except the boxes. BTW, they also came with covers and hardware. The main power lead to a battery bank has not been connected in this picture.

Now this I like. I may use the plain junction box like I did for my combiner on my roof.

[westend]

I made three of these bus boxes. In this picture you can see three device leads and their individual fuses. It is a 4" outdoor junction box with two pieces of HDPE used as standoffs for the copper bar. I had everything on hand except the boxes. BTW, they also came with covers and hardware. The main power lead to a battery bank has not been connected in this picture.

[Calkidd]

4X4Dodger wrote:

Calkidd wrote:
You can use the single post like this....

I know you meant well but this set up is a recipe for disaster or fire.

If the ONE nut comes loose you would have a very bad situation.

The positive cables should be run to a bus bar with each it's own post, secondly they should be fused at about 50 amps.

The post with the Fisheries Supply link is the right way to do this kind of thing...safely and professionally.

Sorry you feel this way. The nut loosing senario can be played with any situation whereas there is a nut and a post. Any of them can loosen, but that's why they invented lock washers. Additionally, there is only one hot lead coming to this post.

[DrewE]

There's no need to fuse the negative lead of the batteries. Just connect them to the chassis ground system with a connection capable of carrying the net sum of any possible battery current. In simplest terms, this means use the same size wire for the negative ground connection as for the positive connection to the bus bar. (Generally there's also no need to have a great many connections to the negative battery pole.)

An overcurrent protection should be used whenever you have a source that could supply more current than the following wire can safely carry. Typically, with a bus bar, this would mean a large main fuse or breaker close to the battery (for these sorts of things, the battery is generally assumed to be able to provide infinite instantaneous current...which is a bit of a simplification), and then individual fuses or circuit breakers suitably sized for the wires and loads that connect to the bus bar.

Arguably, one possible exception to this general rule for fusing might be the breakaway trailer brake system, if applicable. That sometimes is run unfused, on the theory that it is safer to have the brakes unable to be defeated by a blown fuse than to have the safety from fires caused by short circuits that a fuse provides. I've seen pictures where this is done in either way, though I personally would prefer it with a fuse or circuit breaker.