Type of cables to use for connecting 6v batteries?

Huntindog wrote:
...solid connections. Though they are cheap and conduct well, the trade off (there always is one) is that they are not flexible. Road vibrations can cause stress on the battery posts.

I agree. Before doing mine I made sure the batts were very snug in the tray, and checked them often.

Steel on 6-6v batt series interconnects was no problem for me. It's not like they were carrying hundreds of amps.

But I realize all new things must be subject to flak.

Steel is also having higher resistance, what in some situation can get it pretty hot.

2 gauge cable 9" in length can successfully carry 1,000 amperes and not even blink. I used to rip out the insane 2/0 battery post snapping interconnects on big rigs and replace them with 2 gauge welding cable. The trucks went on to spin 855 Cummins engines at 12-volts in -20F winter mornings.

The only issue with using steel is everyone is not fastidious about keeping cables and connections perfectly clean. I have seen oxidized steel interconnects melt lead posts down to molten globs.

Kayteg1 wrote:
What I found much more convenient are copper plates connecting the batteries before big cables go to the coach.

Good plan. I used 1" wide steel bar, cut and drilled to size.

I found the cables always giving me headaches for one reason or the other.
What I found much more convenient are copper plates connecting the batteries before big cables go to the coach.
You can find copper hangers in plumbing dept. or a piece of 1/2" copper pipe hammered flat works well.

Here is a link to the correct way to connect the 4 batteries is series parallel and why.Smart Gauge
Keep the series wires as short as possible to reduce volt drop.

You certainly don't need large cable for charging devices, but you may, depending on what the appliances are. It's always good to know exactly what it is you'll be running.

DrewE wrote:

jayspi wrote:

dcg9381 wrote:
Thanks for that link.

OP: You're running 6v batteries in series. Your battery connections need to at least match your output, so 6ga is right. 4ga is fine.

If you use that inverter, you'll have to go to 2ga, so something to consider for now.

I, like others, use a real battery disconnect unless you've got the holy-grail of RVs with no parasitic draw.

We'll, I already got the inverter. Are you saying that I'll need to 2 gauge for the series/parallel cables (4 cables)? Or for the cables back to the RV as well (6 cables)? If so that's not a problem, I guess I'll have to order them though. I can't find anyone local who has 2 gauge.

The series/parallel cables should be 2 gauge, as should the wires to the inverter. If there are separate wires going to other things in the RV, they only need to be sized (and fused or protected with circuit breakers) for the current that they would be carrying; 4 or 6 gauge to the DC distribution panel and converter might be acceptable, depending on their length and the size of the house loads and so forth.

DrewE wrote:

jayspi wrote:

dcg9381 wrote:
Thanks for that link.

OP: You're running 6v batteries in series. Your battery connections need to at least match your output, so 6ga is right. 4ga is fine.

If you use that inverter, you'll have to go to 2ga, so something to consider for now.

I, like others, use a real battery disconnect unless you've got the holy-grail of RVs with no parasitic draw.

We'll, I already got the inverter. Are you saying that I'll need to 2 gauge for the series/parallel cables (4 cables)? Or for the cables back to the RV as well (6 cables)? If so that's not a problem, I guess I'll have to order them though. I can't find anyone local who has 2 gauge.

The series/parallel cables should be 2 gauge, as should the wires to the inverter. If there are separate wires going to other things in the RV, they only need to be sized (and fused or protected with circuit breakers) for the current that they would be carrying; 4 or 6 gauge to the DC distribution panel and converter might be acceptable, depending on their length and the size of the house loads and so forth.

OK, I think it's clicked with me now :). There were too many comments for me to reply to each one individually, but thank you all for the help!

I ran all over town this evening and couldn't find anyone with 2 gauge cables with the 3/8 connectors on both ends. Fortunately Amazon has some with same day delivery. I think I'll get four 12 inch ones (the shortest they have) for connecting the batteries, and then two 36 inch ones to replace the 6 gauge wires that are connecting the current battery to the RV. The wires are cheap and the connectors are corroded so might as well replace them.

We're convoying up to Alaska with some friends and there was a little miscommunication regarding the schedule. I thought we were leaving on the 15th and they thought we were leaving on the 8th. The 8th it is, and now I'm scrambling to get all of this done by tomorrow! I'm excited about going, but I hate feeling rushed when it comes to this stuff. I was planning on having all next week to do it.

Anyway, I think I have what I need now. I'll post back and let you all know how it goes.