Quick question on wiring acces. to parallel batteries

[68camaro]

Hello, If I have three 12v batteries wired in parallel, can I split the accessories positive wires among two different positive battery terminals, or do I need to connect all positive cables to the same positive battery terminal?

I ask because I need longer SS bolt to put all positive connects on the first battery terminal and my local Lowe's out of size I need......they have all others.....just not mine., go figure. So I figure I can split positive wires among two positive terminals to achieve desired result. As you can see I am very inexperienced in this.

Any flaw in my thinking?

 

[68camaro]

While I am at it, does washer placement matter when I have like 3 - 6 wires to a terminal?

 

[CMARJEEP]

Best practice would be to connect accessory positives to one end of the battery bank and accessory negatives to the battery on the other end of the bank. Of course it depends how you have the batteries wired together.

With that many accessories you should have a separate fuse panel or at least terminal block to wire everything to and then only one set of wires to the batteries from the fuse panel to batteries.

I think method 2 from this link is the best:

SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

 

[68camaro]

Best practice would be to connect accessory positives to one end of the battery bank and accessory negatives to the battery on the other end of the bank. Of course it depends how you have the batteries wired together.

With that many accessories you should have a separate fuse panel or at least terminal block to wire everything to and then only one set of wires to the batteries from the fuse panel to batteries.

Thanks, as I was putting together I thought the same thing. I assume I can use fuse block for negative as well since my negative wires will not reach far battery?

Any recommendations on who makes good fuse blocks?

 

[CMARJEEP]

Thanks, as I was putting together I thought the same thing. I assume I can use fuse block for negative as well since my negative wires will not reach far battery?

Any recommendations on who makes good fuse blocks?

Blue Sea makes a high quality fuse block. And yeah they make them with ground in many different sizes.

 

[68camaro]

Best practice would be to connect accessory positives to one end of the battery bank and accessory negatives to the battery on the other end of the bank. Of course it depends how you have the batteries wired together.

With that many accessories you should have a separate fuse panel or at least terminal block to wire everything to and then only one set of wires to the batteries from the fuse panel to batteries.

I think method 2 from this link is the best:

SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

That link was hugely helpful, thanks.

 

[68camaro]

Do I need a fuse block or could I use a buss bar? I need to connect the 8 positives to it and then have that connect to first batteries positive terminal. I think the positives have fuse upline.

 

[CMARJEEP]

Do I need a fuse block or could I use a buss bar? I need to connect the 8 positives to it and then have that connect to first batteries positive terminal. I think the positives have fuse upline.

If all the accessories are already fused inline you could just use a bus bar or terminal block. But typically you want the fuses as close to the battery as possible and a fuse block makes it easier to diagnose issues and replace blown fuses.

 

[68camaro]

I reconnected all six positive cable to first positive battery terminal post, and order longer 2 AWG black cable to run to far battery negative post per CMARJeeps link according to Method 2.

My positive terminal looks pretty crowded with six connectors not sure if great setup.. Would the Blue Sea 250 AMP 6 stud bus bar linked below be correct for my needs? Also, since I have 6 cables that will connect to bus bars 6-studs, I will not have a free stud to connect to battery, do I double up leads on one stud to leave a free stud to connect to battery?

Blue Sea MaxiBus Amp Electrical Bus Bar, 6 Stud

The Blue Sea Electrical Bus Bar (6 Stud) consolidates multiple wires or circuits. It gives you easy access to multiple wires on a single stud.

www.wholesalemarine.com

Big thanks in advance.

 

[broncobowsher]

Never run all the batteries to a common point. Unless you can get the cables the same length all the time. Voltage drop from different cable lengths will load/charge the batteries at different levels. There is a way around this. For a 3 battery setup (same applies if you have more or less) take the single load/charge positive cable to battery 1, jumper from 1 to battery 2, and another jumper from 2 to 3.
Ground is the opposite. Jumper from 1 to 2, 2 to 3, 3 to the load/charge. What this does is evenly distribute the voltage drop through all the batteries. Battery 1 has a direct feed off the positive, but two jumpers to ground. Battery 3 has two jumper to positive, but a direct feed to ground. Battery 2 has a single jumper on each, so a total of two. This will do a much better job of keeping the batteries balanced.

This also eliminates the stack of cables on a single point (and you super long bolt needs). You can disconnect the battery bank with a single cable.

 

[DiploStrat]

You may want to read this: http://www.smartgauge.co.uk/batt_con.html