advice on 800w 24v system

[jBrew]

+ what size wire should i use to connect batteries to make a 2S2P total of 24v 200ah?
+ is it ok if the wire is longer on the negative and shorter on the positive (wire sizes and lengths included in the image)?
+ fuses? other then the 12v fuse block

 

[Zwy]

What are using the original converter for? DC to AC to DC will have major losses.

I looked again, you have a 24V to 12V buck converter. Ignore above.

 

[OffGridInTheCity]

+ what size wire should i use to connect batteries to make a 2S2P total of 24v 200ah?

I think I see a 1200w/24v = 50a inverter + a 40a dc->dc converter. So let's say 60a max current from the battery side.
You might get by with 6awg but 4awg would do it. I like to use 'welding wire' such as this - https://www.ebay.com/itm/302358586963?hash=item4665f9e653:g:PtkAAOSwvflZTCWw - as it bends easily and I like to use red for + and black for - everywhere.. as a personal safety issue that you NEVER touch red to black and it will help reduce shorts

+ is it ok if the wire is longer on the negative and shorter on the positive (wire sizes and lengths included in the image)

If you go with 4awg... its 'slightly' better to keep lengths the same... you can loop one of the wire and twist tie it off to do this. On the other hand - 6ft for one and 12ft for the other is not the end of the world.

+ fuses? other then the 12v fuse block

Absolutely. You might consider circuit-breakers so they can double as on/off switches. You want this from battery -> each load, sized for the wire size. I like to have one between the charge controller and the battery bank. This will give you a way to disconnect *everything* from the battery bank to work on it. And I like to have a circuit breaker (or simple switch) as the PV comes into the charge controller - so I can just easily disconnect PV current to work on the charge controller.

 

[jBrew]

Thank you for the tips

I think I see a 1200w/24v = 50a inverter + a 40a dc->dc converter. So let's say 60a max current from the battery side.
You might get by with 6awg but 4awg would do it. I like to use 'welding wire' such as this - https://www.ebay.com/itm/302358586963?hash=item4665f9e653:g:PtkAAOSwvflZTCWw - as it bends easily and I like to use red for + and black for - everywhere.. as a personal safety issue that you NEVER touch red to black and it will help reduce shorts

i'll definetly will go with the 4AWG to wire up the batteries

If you go with 4awg... its 'slightly' better to keep lengths the same... you can loop one of the wire and twist tie it off to do this. On the other hand - 6ft for one and 12ft for the other is not the end of the world.

looping the extra wire is a great idea

Absolutely. You might consider circuit-breakers so they can double as on/off switches. You want this from battery -> each load, sized for the wire size. I like to have one between the charge controller and the battery bank. This will give you a way to disconnect *everything* from the battery bank to work on it. And I like to have a circuit breaker (or simple switch) as the PV comes into the charge controller - so I can just easily disconnect PV current to work on the charge controller.

found a bunch of circuit breakers on amazon for the fuses, unless you know a better site i can get them

here is the updated system:


if i'm running a 500w appliance will the 6AWG wire between bank and DC->AC converter be enough? or should i go with something thicker?

 

[OffGridInTheCity]

Just one comment on the 35a solar panels fuse. The solar panels will produce a max of 12a. And just fyi - panel 10awg / MC4 connectors max out at 30a. So I'd go 15a or 20a instead of 35a as 35a is too high to protect the wires


------ A tip from further down the road that works for me....
I know it costs $, but I find it convenient/worth it to have a 'control box' w/circuit breakers in my trailer. A central place to 'fuse' but also to just turn key components of the solar system on/off.

I use Midnite Solar (dc) circuit breakers in a combiner box (w/buss-bars). The breakers are UL (high quality), snap onto a DIN rail, and come in a wide variety - 5, 10, 15, 20, 30, 50, etc.... of amps. Here's a 15a model https://www.amazon.com/MidNite-Solar-MNEPV15-Midnite-Solar-MNEPV15/dp/B007IAAGPE

 

[jBrew]

Just one comment on the 35a solar panels fuse. The solar panels will produce a max of 12a. And just fyi - panel 10awg / MC4 connectors max out at 30a. So I'd go 15a or 20a instead of 35a as 35a is too high to protect the wires

thats a good point LOL

------ A tip from further down the road that works for me....
I know it costs $, but I find it convenient/worth it to have a 'control box' w/circuit breakers in my trailer. A central place to 'fuse' but also to just turn key components of the solar system on/off.

I use Midnite Solar (dc) circuit breakers in a combiner box (w/buss-bars). The breakers are UL (high quality), snap onto a DIN rail, and come in a wide variety - 5, 10, 15, 20, 30, 50, etc.... of amps. Here's a 15a model https://www.amazon.com/MidNite-Solar-MNEPV15-Midnite-Solar-MNEPV15/dp/B007IAAGPE

View attachment 56934

this will definitely keep things organized. Thanks

 

[bobdelso]

thats a good point LOL

this will definitely keep things organized. Thanks

I use automatic reset circuit breakers in my setup as its pretty hard to reach.