Simple joining of two batteries in parallel

[rikhall]

Simple question re mechanics, not electron flow

- to join two 12 v marine batteries in parallel I just go from neg to neg and then on to the shunt and from pos to pos and then on to #1 terminal on the switch.

I hear "Never put two wires on the battery post" so do I need something that "looks" like this???

*** I KNOW THIS IS NOT IT - illustration purposes only - I KNOW this is a terminal insulator ***



Or do I need to go from neg to a bus bar and the other neg to a bus bar and then from the bus bar to the shunt etc.

Thanks

Rik

[Maine Sail]

Rik,

I don't know where you ever heard don't put two lugs on a battery post but nearly every boat our there with series or series parallel has two lugs on one post and it's a non-issue. Much more than two, with the heavy duty lugs, and the threaded post can get rather short.

[sailingdog]

If you want to minimize the number of lugs on a post, use something like this:




IIRC, the ABYC spec says no more than FOUR connections/terminals/lugs per screw or battery post..

[fairbank56]

From ABYC E-10 Storage Batteries

10.8.4
Multiple conductors connected to a battery shall be installed with the highest ampacity conductor terminal closest to the battery, followed by successively smaller ampacity conductor terminals.

10.8.4.1
A maximum of four conductor terminals shall be permitted to be installed on a single battery stud.

[sailingdog]

Originally Posted by fairbank56

From ABYC E-10 Storage Batteries

10.8.4
Multiple conductors connected to a battery shall be installed with the highest ampacity conductor terminal closest to the battery, followed by successively smaller ampacity conductor terminals.

10.8.4.1
A maximum of four conductor terminals shall be permitted to be installed on a single battery stud.

As I said, four terminals per post.

[rikhall]

Originally Posted by Maine Sail

I don't know where you ever heard don't put two lugs on a battery post.

Super, thanks. At my age I don't always remember where I think, maybe, that I heard things.

As always, thanks

Rik

[funjohnson]

You could always use one of the Bluesea terminal fuse blocks with two studs.

[Stu Jackson]

And Blue Seas makes what they call a Power Post (and a Power Post plus) that can can use to gang bunches of wires together, like a bus bar but one big post.

[rikhall]

Or I could just put "two lugs on one post and it's a non-issue"

Thanks all.

I just spent a bunch on-line getting the stuff I need.

Shalom

Rik

[sailingdog]

Originally Posted by funjohnson

You could always use one of the Bluesea terminal fuse blocks with two studs.

That's not really designed for that purpose AFAIK. It is designed if you have a single battery feeding two loads, so that the wiring for each load can be properly fused at the battery. He has two batteries feeding a single load.