Inverter Cable

[sunshine 1]

I have been thinking about to get 2 Battle Born lithium batteries, so I went into Am solar website. They said the cable size from batteries to the inverter needed to be 4/0. I am thinking wow, my cable is only 6 Gage from my batteries to my xantrex 2000 watt inverter.On the website it said there need to be a fuse on the positive cable. On my installation there is no fuse. I am so upset that a professional installer like Camping World would do that kind of installation.
I have used my inverter to run my microwave for 2 years, so am i lucky that nothing bad has happened??
I went into xantrex website they recommended 2/0 cable. I dont even know if a 4/0 cable would go into my xantrex 2000 freedom inverter, anybody know?

[rohrmann]

It depends on what the temperature rating of the cable insulation is, the higher rating effects the amp rating. If you use a higher temperature rated cable you can use a smaller cable. If I'm figuring this correctly, for 2,000 watts, you need almost 170 amps of cable capacity at 12 volts.
https://www.cityelectricsupply.com/d...ty%20Chart.pdf

[sunshine 1]

Thanks, for your response. It says on the cable "SAE J1127 SGT TYPE2 60V & SAE J378 60V 6GA 105 C (221 F) DRY". It is a 6 gage cable
I tried to google to see the amp. rating. I could only find that the cable was rated up to 120 amps. My 2000 watt inverter need like you said 170 amps. Plus there is no fuse between the battery and the inverter.

[rohrmann]

I really think there must be a fuse or a breaker installed, or if in the unlikely event of a short or other failure, you can have a nasty explosion of the batteries being connected to an unprotected problem. I think you will see, even on the rigs with a residential fridge with an inverter, there is an additional breaker that is near the batteries on the lead going to the inverter. This is copied from the installation manual:


DC Disconnects and Over-Current Devices The DC circuit from the battery to the inverter/charger must be equipped with a disconnect and over-current protection device. (Refer to your applicable installation code.) Type-This device usually consists of a circuit breaker, a “fused-disconnect,” or a separate fuse and DC disconnect. Do not confuse AC circuit breakers with DC circuit breakers. They are not interchangeable. Rating-The rating of the fuse or breaker must be matched to the size of cables used in accordance with the applicable installation codes. Location-The breaker or fuse and disconnect should be located as close as possible to the battery in the positive cable.Applicable codes may limit how far the protection can be from the battery.


It also shows, along with the 4/0 cable that a 250 amp fuse or equivalent must be installed on the DC cable. I know from experience that 4/0 copper cable is extremely difficult to work with in a tight space, but there are much more flexible 4/0 cables, similar to welding cable, that can be used that would make it's use easier. Use of terminals on the cable will need to be compression type connectors which will need the appropriate press to complete the connection. even if the cable size isn't increased, it will still need a fuse or breaker to be installed.


https://www.xantrex.com/documents/Inverter-Chargers/Freedom-SW-2000/Freedom%20SW%202000%20InvChg%20Install%20Guide(975-0527-01-01_Rev-C).pdf

[sunshine 1]

Rohrman, I have said in my 2 posts that I have no breaker or fuse between my batteries and inverter. Why are you question me and say I have?????
I can see the cable going from my positive battery terminal into my inverter, with no fuse or breaker between.

[mhs4771]

I think he's questioning it because it's extremely dangerous to be running that type of connection without some sort of protection. If something were to happen you could very easily have over heated wires causing a FIRE.

[AZ Traveler]

Tommy,

Its not that hard to install heavier cables and a fuse. Sounds like a poor aftermarket install. Good catch.

[rames14]

Good job on doing your research. I believe I had a 250 amp blade fuse on my 2000 watt Xantrex. It was installed by my dealer and I believe they used 2/0 wire. It was about a 2 foot run. I am anxious to try out my Battleborn (Dragonfly) batteries. Make sure to set your Xantrex charger to lithium.

I would go back, now that you are armed with your new knowledge, and have CW fix their mistake. You already paid to have it installed correctly. Good luck.

[sunshine 1]

yea, that is why I am so upset with CW installing it w/o a fuse

[sunshine 1]

Yeah, thats why I am so upset with CW. I didnt have the knowledge I have now to catch it 2 years ago.

[sunshine 1]

Yeah, I did not have the knowledge I have now to catch what they did 2 years ago installing it. Thats why I am upset now, knowing what disaster that could have been.

[sunshine 1]

I would not go back to CW I think they are incompetent , I bought my montana there but have had so much troubl repairing things there.

[sunshine 1]

Thanks Zack and Ron for helpful information

[Gaetan]

Originally Posted by sunshine 1

I have been thinking about to get 2 Battle Born lithium batteries, so I went into Am solar website. They said the cable size from batteries to the inverter needed to be 4/0. I am thinking wow, my cable is only 6 Gage from my batteries to my xantrex 2000 watt inverter.On the website it said there need to be a fuse on the positive cable. On my installation there is no fuse. I am so upset that a professional installer like Camping World would do that kind of installation.
I have used my inverter to run my microwave for 2 years, so am i lucky that nothing bad has happened??
I went into xantrex website they recommended 2/0 cable. I dont even know if a 4/0 cable would go into my xantrex 2000 freedom inverter, anybody know?

With a 2000 watt. Inverter you will need a 200 amp fuse. As far as wire in order to minimize power loss recommend gauge 01 welder cable.

[firestation12]

Consider using welding cable for your project. In short lengths, it can supply your needed amperage in much smaller wire gauges. Electrons travel on the circumference of wire. Because welding wire has many more strands in it's cross section which gives it superior surface area. #2 welding cable (not to be confused with 2/0) will suffice for your two 100 amp battleborn batteries. As stated by others, you'll want install fused protection. Rohrmann mentioned the wire's temperature rating that can affect the useful ampacity. Duty cycle is also another consideration. How much and for how long are you planning to draw from that 2000 watt inverter. 2000 watts draw on your 12 volt batteries, is about 166 amps. If you were to draw a full 2000 watts from your batteries, they will be expended in a little over and hour 15 minutes. Your system is best suited for running a microwave or hair dryer briefly, TV, USB, or other electronics for more extended periods. Short duty cycle items are a wise choice for your size storage plan. When selecting solar panels to complement the 200 watts of BB batteries, remember that for example, a 300 watt panel typically yields only 80% of that, and only at peak sunshine. My 5000 watt panels rarely achieve 4000 watt output. Ambient temperatures influences efficeincy. Summer heat diminishes panel efficiency, winter coolness increases it, but there is less hours of sunshine. Too many times I see undersized panels installed to maintain the batteries. If I were you, I'd fix the problem myself. You could hold Camping World feet to the fire, but might have to leave the camper for weeks. Will Prowse has many YouTube videos on LifeP04 battery projects. Good luck!

[Sokcap48]

I have 4 Trojan T145 batteries. I went with 4/0 cables. I ordered mine with ends attached.
( lazy ) and I know they are on there properly. I run solar all winter, 600 watt panels, 2000 watt Renogy inverter and 60 amp mpg controller. And you NEED to fuse between battery bank and inverter. Do not use those flat snl fuses. Use this:

https://amsolar.com/rv-inverter-accessories/95f-clst.

It is also recommended to fuse between solar panels and battery and between battery and solar controller. Hope this helps now or in the future.

[rohrmann]

Just to avoid a misunderstanding about how electricity flows in a wire, electrons in the atoms of the actual metal wire are what moves, either back and forth for AC current or in one direction like in DC current, but they do not travel on the outside of the wire. The more metal wire, either in larger strands or more smaller strands, increases the amount of metal conductor which increase the amount of amps that can flow in the wire. This discussion might help any that are interested. https://greencoast.org/how-electrici...through-wires/

[sunshine 1]

Thanks Guys, I actually ordered 3 100 ah batteries from Battle Born. I have 720 watts solar on the roof +200 watts portable on the ground. I ordered a 400 A Fuse kit between batteries and inverter. I will use 2/0 cable from batteries to the inverter and 2 gage cable between the batteries.
No I don't want to take my trailer back to CW. Last time I had it there for repair for over a months, they had left one light on in the trailer, my 3 agm batteries total 315ah was dead. Registered 10 volts on my volt meter. I was able to get them back to life with my CTEK charger.

[firestation12]

Originally Posted by rohrmann

Just to avoid a misunderstanding about how electricity flows in a wire, electrons in the atoms of the actual metal wire are what moves, either back and forth for AC current or in one direction like in DC current, but they do not travel on the outside of the wire. The more metal wire, either in larger strands or more smaller strands, increases the amount of metal conductor which increase the amount of amps that can flow in the wire. This discussion might help any that are interested. https://greencoast.org/how-electrici...through-wires/

The link given above doesn't clarify the question of does the current flow on the perimeter or evenly through the interior of a wire (like water through a pipe. Here is a link to a discussion between electrical wizards discussing in depth how electrons flow through wire in ALTERNATING CURRENT VS DC. In the link, the term of skin effect is coined for LOW FREQUENCY ALTERNATING CURRENT. I have to thank Rohrmann for sending me back to internet school as time had erased the fact that some of the electrons use the wire core, not just the perimeter. For the sake of this thread though, DC current uses the entire cross section of wire.



https://physics.stackexchange.com/qu...n-the-interior


Below is an excerpt of one of the commenters. I also found interesting that long distance transmission wires have steel cores for strength clad with an efficient conductor. Copper clad wiring and conductive plates are still manufactured and sold.




Quote begins:


I'd rather have just commented, but since I got an account here just because of this, I will attempt an answer, but cannot help but try to redirect some of the commentary here.
Simple answer: Yes, in an ideal case. If you construct the model you will see that that current density shrinks to zero at the centerline of the conductor, where E vector is zero. This takes some work beyond the statement of Maxwell's Equations.
Reality is of course not so cut and dried. But the gradient of current density is still very significant. Do you want to know why Nikolai Tesla could demonstrate the phenomenon using his own body? Well, here you have it.
So, use stranded wire for speaker cables, ipod jacks, etc. It's total current capacity (due to heat) is lower, so don't wire your house with it.
Finally, the separation of power transmission lines is to reduce losses due to capacitive coupling. But while we're on the subject, check out Hoover Dam. There you can buy a section of the original transmission line from the dam to the grid. It's copper, made of interlocking radial cross-section parts. And yes, it's hollow. For 60Hz.

[rohrmann]

We had some hollow stranded copper transmission cable that had a twisted ribbon inside as the core to maintain the round shape, but the hollow design was strictly to provide added cooling, and this stuff was a real pain to work with, so it isn't widely used anymore. I also worked with 500,000 volt transmission cable that the size was 2,300,000 circular mils, also designated as 2.3 mcm cable, aluminum that was almost 2" in diameter, stranded, and no steel core, and rated over 1500 amps. The steel core in some aluminum cable allows the temperature rating of the wire to be higher due to load so it won't melt it apart like all aluminum wire would. It's pretty amazing what is used to move electricity around the country to get electric power to us.