Wire Source

[o1marc]

Looking for cables for the battery to inverter. 4/0 is recommended. I'm only finding it in the $8+/ft range. I guess I need to keep that inverter as close to the batteries as possible. Anyone know of a inexpensive source for cabling?

[PNW_Steve]

4/0?

Holy cow, what kind of inverter and battery bank are you running?

Mine calls for a minimum of 6ga. for a 2% or less voltage drop under full load.

I plan on going 4ga. To give me some headroom.

Here is a wire sizing calculator: https://www.wirebarn.com/Wire-Calculator-_ep_41.html

I would double check the requirements for wire size before spending $8 a foot.

Edit: You definitely do not want to undersize your wiring. That said, there is no reason to pay for 4/0 when a less expensive (smaller) MAY work just as well.

[o1marc]

Originally Posted by PNW_Steve

4/0?

Holy cow, what kind of inverter and battery bank are you running?

Mine calls for a minimum of 6ga. for a 2% or less voltage drop under full load.

I plan on going 4ga. To give me some headroom.

Here is a wire sizing calculator: https://www.wirebarn.com/Wire-Calculator-_ep_41.html

I would double check the requirements for wire size before spending $8 a foot.

Edit: You definitely do not want to undersize your wiring. That said, there is no reason to pay for 4/0 when a less expensive (smaller) MAY work just as well.

I checked several sites specifically on what size wire from the battery to the inverter, all of them say 4/0.

[o1marc]

Originally Posted by PNW_Steve

4/0?

Holy cow, what kind of inverter and battery bank are you running?

Mine calls for a minimum of 6ga. for a 2% or less voltage drop under full load.

I plan on going 4ga. To give me some headroom.

Here is a wire sizing calculator: https://www.wirebarn.com/Wire-Calculator-_ep_41.html

I would double check the requirements for wire size before spending $8 a foot.

Edit: You definitely do not want to undersize your wiring. That said, there is no reason to pay for 4/0 when a less expensive (smaller) MAY work just as well.

I checked several sites specifically on what size wire from the battery to the inverter, all of them say 4/0.
I have a 3000/6000watt inverter, but will probably use the 3500/7000 one I took out of the TC2000.
Just found some on Amazon for around $4.50

[PNW_Steve]

Originally Posted by o1marc

I checked several sites specifically on what size wire from the battery to the inverter, all of them say 4/0.
I have a 3000/6000watt inverter, but will probably use the 3500/7000 one I took out of the TC2000.
Just found some on Amazon for around $4.50

That is a monster inverter. What do you have for batteries, charger and solar do you have backing that up?

When I documented my loads I found that an 1800 watt inverter was plenty. I have a Xantrex 1800 that will surge to 2900. It draws 75 amps at rated max and about 120 amps at Max surge.

Regarding the wire on Amazon: be careful that it is not copper plated aluminum. I almost ordered some thinking that I was getting a bargain. A little research made it clear that this was not the all copper, high strand count that I want for my battery cables.

[o1marc]

Originally Posted by PNW_Steve

That is a monster inverter. What do you have for batteries, charger and solar do you have backing that up?

When I documented my loads I found that an 1800 watt inverter was plenty. I have a Xantrex 1800 that will surge to 2900. It draws 75 amps at rated max and about 120 amps at Max surge.

Regarding the wire on Amazon: be careful that it is not copper plated aluminum. I almost ordered some thinking that I was getting a bargain. A little research made it clear that this was not the all copper, high strand count that I want for my battery cables.

It's copper.

https://www.amazon.com/TEMCo-WC0341-...202739518&th=1

[john61ct]

High ampacity cabling of that capacity is indeed very expensive.

Use Blue Sea' Circuit Wizard to check if you really need as thick as you think you do.

That is very thick, I've had to use it, but rarely more than 30' at a time.

If you're going to spend big bucks anyway, use the good stuff, especially if exposed to harsh conditions

UL1426 105c tinned "boat cable", type 3.

Ancor is well known but over priced

EPM makers of Deka

Pacer

also Berkshire Wire in Western MA, call for nearby distribution

but lots of counterfeiting of all this stuff going through Amazon markets, eBay etc.

Known-good marine supply houses are best to avoid that.

http://www.bestboatwire.com is great, and use their sister co genuinedealz.com for cut to length & custom terminated, top work very reasonable.

Avoid Cobra

You also need to be picky to get quality termination supplies, FTZ and Ancor are great

The right crimpers are expensive! Maybe see if you can find them to borrow (West Marine, local marina / boatyard) or rent, then buy the fittings to match the crimpers available that way.

[o1marc]

When I check converter sizing they always talk about making the list of usage of everything in the bus to see total need, then add 10-20% to the size of the inverter to be sure it is big enough. Question is- can you go too big on the inverter, or is it's output still determined by the battery bank and usage?

[Native]

Originally Posted by o1marc

When I check converter sizing they always talk about making the list of usage of everything in the bus to see total need, then add 10-20% to the size of the inverter to be sure it is big enough. Question is- can you go too big on the inverter, or is it's output still determined by the battery bank and usage?

The A.C. load generally determines the inverter max output needed. It is always better to have more inversion capability than needed, but not extremely more.



I also have a 3000W/6000W inverter/converter and it specifies 4/0 cable. However, you can run two strands of 2/0 and have an equivalent of 5/0 ... a touch of safety margin and the cables are easier to manipulate. Even 2/0 is tough ... I could not imagine 4/0!

[o1marc]

The inverter had wires coming up through the floor at the battery box that were about 4" long and at least 3/4" thick. I haven't been able to get into the battery box as the seller has not sent me the extra keys he has. I need to remove the 2 house batteries and cables to the inverter. I may have the bus sold tomorrow, so I will take the 5/16" tech screws off the hinge end of the battery door tomorrow and get them out. Hope the seller doesn't stiff me on the keys and remote for the inverter.

[Native]

Originally Posted by o1marc

The inverter had wires coming up through the floor at the battery box that were about 4" long and at least 3/4" thick. I haven't been able to get into the battery box as the seller has not sent me the extra keys he has. I need to remove the 2 house batteries and cables to the inverter. I may have the bus sold tomorrow, so I will take the 5/16" tech screws off the hinge end of the battery door tomorrow and get them out. Hope the seller doesn't stiff me on the keys and remote for the inverter.

I take it you are not selling it with the inverter then.


If you sell it tomorrow, will you forward the keys or just the old owner's contact info?

[o1marc]

Originally Posted by Native

I take it you are not selling it with the inverter then.


If you sell it tomorrow, will you forward the keys or just the old owner's contact info?

I emptied the bus and kept the TV, solar panels, controller, inverter, mini fridge for myself. That bus still needs to be gutted for conversion so I just cleaned it up to flip as is. I'll do both, forward the keys when I get them and give the new owner the old owners contact. The seller was quick to answer the phone when he was in a bind. Now that he's been paid I can't get through and he's not replying to texts.

[PNW_Steve]

Yes, you can go too big on the inverter.

All inverters consume some power all of the time even with no load. Larger inverters use more power when idle than smaller ones. I have seen people install a ridiculously large inverter only to find that the inverter itself would drain the batteries overnight.

[john61ct]

If energy efficiency is a concern, that drops dramatically with smaller loads running off a big inverter.

Also any inverter should be turned off when not in use.

My reco strategy in that case is DC native avoid inverters as much as possible, where not then multiple small ones, even dedicated per load device.

Much cheaper too, and gives redundancy

[Jolly Roger bus 223]

Check the prices at your local welding supply store.
Weld lead/cable is softer,more flexible,easier to work with and triple the strand runs in the jacket than a standard 4/0 for electrical wiring and the franchise type supply stores will have lug style connectors or they can crimp them for you right there.
For the prices you are seeing I would make it easy and get welding lead for the same price range

[o1marc]

Originally Posted by Jolly Roger bus 223

Check the prices at your local welding supply store.
Weld lead/cable is softer,more flexible,easier to work with and triple the strand runs in the jacket than a standard 4/0 for electrical wiring and the franchise type supply stores will have lug style connectors or they can crimp them for you right there.
For the prices you are seeing I would make it easy and get welding lead for the same price range

The link I posted shows it is labeled as heavy duty welding cable.

[Jolly Roger bus 223]

Sorry? I didn't open the link?
I ain't a big fan of Amazon for important stuff like this. I want to physically see it before I buy it?
I just replaced 2-300' Leeds on my machine cause I didn't get the life expectancy out of the better deal leed that I bought 2- years ago?
Normally get 6-years on my big machine with quality Leeds.
About 40% cheaper but not if you have to replace every two years verses 6

[o1marc]

Originally Posted by Jolly Roger bus 223

Sorry? I didn't open the link?
I ain't a big fan of Amazon for important stuff like this. I want to physically see it before I buy it?
I just replaced 2-300' Leeds on my machine cause I didn't get the life expectancy out of the better deal leed that I bought 2- years ago?
Normally get 6-years on my big machine with quality Leeds.
About 40% cheaper but not if you have to replace every two years verses 6

Whats not to like, it's made in the USA and meets my requirements. How do you tell the difference between this and your "quality" leads?

[Jolly Roger bus 223]

No link so I can't tell?
My last ones were bought online and don't know where from?
My newest I went to my local weld supplier and bought what I needed?
Do you have a national welder there or a machine welding?
National is changing to air gas and ARC3.
You pay a little but they have it when you need it

[PNW_Steve]

I installed the electrical system & solar for a friend on his bus. He ordered most of the materials himself and found battery cable called "super-flex".

It was 1/0 and was soooooo easy to work with!