I'm updating the main electrical components in my Motorhome and in the process I have to run new 12v cabling for the DC side of the remodel.
I'm installing 10 Lifeline, 6v, L16 AGM 400amp hrs@20 duty cycle. batteries for the house side. I will tie them together and run them to my Victron 3000 watt inverter charger.I will also have about 2000 watts of solar tied into the system.
I plan to use 4/0 cabling for all my runs.

My question; I can use standard 4/0 copper cabling or Marine grade,tinned 4/0. The area where the electronics and cabling will live is in a insulated bay that is not exposed at all to the environment outside. perhaps some condensation that's it.
The factory installed wiring for the old system was in a sheltered bay but the bay was more exposed to outside elements because flooded wet cell batteries were used and a good ventilation system was needed to vent the out gassing. The factory installed tinned copper cabling.
Do you think I should spend the extra money for the tinned wire or will regular copper weding cable work fine?
Thanks for your advice.

Use the tinned wire to help prevent corrosion especially at terminals. I think AGM batteries do have a small amount of out gassing and need some outside ventilation.
Give thought to how you will connect the wire to the batteries and other equipment. Long term - greased bolted connections with compression lugs are best I think.

I would go with tinned whenever possible. Check out Genuine Dealz for some decent pricing.

There are other similar sites that may have better pricing. I have bought wire from them for years.

4/0 are you building a locomotive?

Plain copper is fine. I am not an expert, but yes actually i could be considered an expert.

Tinned, all day long.

"Tinned, all day long."

please explain why?

quote:

Originally posted by Ishootsometimes:
"Tinned, all day long."

please explain why?

quote:

...is not exposed at all to the environment outside. perhaps some condensation that's it.

Mostly because of the potential for corrosion.

i would also like to hear a "good" reason for the tinned wire as well.

I have a '87 model sailboat, built before tinned wiring was standard on boats. I have never had a system failure due to corrosion failure of the wiring. yes, I agree it "could" cause problems. I just have never witnessed one.

I know. most aviation systems use the tinned wiring. system failure at 30,000 feet would be devastating. But on a boat? or a motor home?

it reminds me of the time I went to West marine to buy a replacement for the steaming light. (only on when under power) and the salesman tried to upsale the new LED replacement bulb. $50 instead of the $5 OEM bulb. why? because it would last longer than a standard bulb.

I had owned the boat for 15yrs and this was the first time it needed replacement. if the new one lasted half as long, I would still be ahead $$.

ymmv

john

Eltonr, thanks for the careful thinking.

However, there is no tin plated wire on a plane. None. Ever.

But think about where you sleep every night. You will find no plated wire in your house . Why is this? It does not need to be.

hi again. Aircraft wire is always Nickel or Silver plated. We can get into the Hall effect and the skin effect another day.

4/0 welding cable, with correct crimped on ends with waterproof heat shrink would work well. It is more flexible than the plastic jacket marine cable and about 1/3 the cost.

If you use dual shield heat shrink, which seals the connection, you should have no problems.

In my old marine repair business I used to buy thousands of feet of marine wire ever year. In this case, tinned wire is not needed. For smaller wire I always used tinned wire.

I'm with C1steve. If you are talking about the 4/0 cables there is no need for tinned. If you are talking about 12v runs of nominal device sizes like 10-16g then you want tinned.

For the purpose of this discussion, let me set forth the circuit under discussion! Not houses, not airplanes, not boats, all which can have different requirements.
It is a high current low voltage D.C. circuit involving multiple expensive batteries and an inverter in a motor home. The use of tinned wire may help limit corrosion at connection points.

How many of you have had to replace battery post connectors or cables on your car? Many times this is due to corrosion, external or internal. I have even seen battery cables melt the insulation on the wire.

quote:

Originally posted by sig operator:
For the purpose of this discussion, let me set forth the circuit under discussion! Not houses, not airplanes, not boats, all which can have different requirements.
It is a high current low voltage D.C. circuit involving multiple expensive batteries and an inverter in a motor home. The use of tinned wire may help limit corrosion at connection points.

How many of you have had to replace battery post connectors or cables on your car? Many times this is due to corrosion, external or internal. I have even seen battery cables melt the insulation on the wire.

This. I would go with Tinned. The Tinned wire will carry current more efficiently over time. The individual strands won't break down and corrode as easily as non-tinned and also the wiring won't heat up as much since you're using it for long periods of serious amperage draw (inverter, not something like a starter that's on for 10 seconds). Also tinned will last longer with the vibration a motor home sees and the bouncing around.

If you need a decent amount of it, Call Pacer Marine in Fort Lauderdale, FL. They're a manufacturer with top quality stuff at prices far below West Marine and marine stores.

Jimmy, please explain.

You are wrong on at least six accounts.

quote:

Originally posted by Ishootsometimes:
Jimmy, please explain.

You are wrong on at least six accounts.

"On the lab bench and under ideal circumstances, the bare copper is going to outperform the `tinned' variety. Too bad it isn't quite that easy. If it was, we would be done, end of discussion. However, you can't have an “age old argument” if the situation is that straightforward. Why the argument then? Well simple, the real world practitioners have experienced different results than the lab testing would suggest. Our own testing has proven both types of copper can be right if you add in the missing variable…time. Fresh, new, bare copper conductor works great. Unfortunately, we have found that it will oxidize much more quickly than the tinned variety which leads to a degradation in electrical performance."
https://www.quabbin.com/tech-briefs/tin-vs-bare

"Did you know that 12-gauge tin coated copper wire can last up to ten times longer than a similar 12-gauge bare copper wire? As tin resists corrosion and doesn’t oxidize the plating helps to protect the copper underneath. This wards off additional wear and tear that would detract years off the life off a bare copper cable. "
https://www.pacergroup.net/pac...pper-vs-bare-copper/

We're talking about an inverter bank and a motorhome with both 2000 watts of solar charging and a 3000 watt inverter/charger..... so the ability to discharge 3000 watts at 120 volts and charge the batteries when connected to shore power.....if the OP is running the battery bank at 12 volts DC that's 276 amps an hour to make 3000 watts at 120 volts a/c providing no conversion losses, but generally there are 15% conversion losses. So you could discharge 325 amps per hour at 12 volts dc (from the batteries) to create 120 volts a/c 25 amps (3000 watts).....that would create a ton of heat in the battery cables.

Generally inverter banks of this size are most commonly 36v and 48v DC to lower the amount of amperage drawn from the batteries which lowers the heat produced in the cables and size of cables required......but there isn't a feasible way to make that from 10- 6 volt batteries. If you series 8 6 volt batteries you get 48 volts. There are no way to series 6 volt batteries to get 36 volts without them being in multiples of 6..... Even if you did 24 volts, it would be multiples of 4 batteries so 4 or 8 batteries, A series of 2 banks of 4 batteries that you parallel both banks together for more capacity. When creating a bank with multiple batteries in series you don't parallel some of the batteries in series and not others as they wouldn't equalize properly. You make banks in series and then parallel the separate banks. But, each bank should have the same number of batteries and battery size.


300amps @ 12 volts DC is equivalent to 75 amps at 48 volts DC, both would make 25 amps/125 volts AC 3000 watts.


I'm not quite sure how 2 sentences can be wrong in 6 different ways?

AGM batteries can be installed in unvented living spaces as well as GEL batteries. Lead acid cannot be.

Thanks Jimmy.

armored,
If the batteries have bolted connections, get new hardware of the correct type. Usually this is stainless steel bolts, nuts and Belville type compression washers. These may be furnished. Also get the recommended type of terminal protection.

Sounds like you have a nice ride.

Hi Jimmy,

Not picking a fight but you are completely wrong.

You had great points and references but this is a Motor home. Not a power station.

Expected life 20 years.

All connections made one time. Spray some s+-&t on them if you don't want them to corrode.

5 sentences btw.