Trying to verify some concerns about the proper gauge wire to use, correct circuit breakers as well as placement?

AndreMatthews

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HELP! I have this rather costly project and am not sure if it is going to work. I have concerns with the gauge of wires to use, the correct type of circuit breakers, and if a busbar should be used or a breaker box with fuses? I know this is a tall order, but any positive assistance would be greatly appreciated. All comments of a negative tone will be laughed about as I know I do not have the actual knowledge for this project, but I am trying to learn. Happy Holidays!Slide1.jpg
 

Supervstech

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Not really enough info here.

Click the links at the top of he forum. Will has multiple schematics for various builds.
 

AndreMatthews

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Not really enough info here.

Click the links at the top of he forum. Will has multiple schematics for various builds.
Ugh, ok, I am not sure how to explain this, so I will say this! I wanted to power a residential fridge in my RV full time on solar, with sure power being a backup. My friend had a 400w solar system he did not use so he sold it to me and I have purchased items I thought would work. My first try seemed successful but in the wee hours of the morning my 2000 W Inverter would start screaming low power and I would turn off the inverter letting the fridge fend for itself until the sun started charging the 400 Ws of Solar Panels I have. Long story short I ended up running two more 100 W panels on the RV roof, positioned the panels in a Parallel configuration, and purchased two lithium EnjoyBot LifePO4 12V 100Ah batteries and a 60A MPPT Solar Power Controller to try and figure this system out. I have also attempted to understand the amount of power this refrigerator needs to ensure I have enough solar power coming in.
 

Supervstech

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Ok, if the fridge is your main load, you should be ok on 4 gauge wire to the inverter, but a 2000W inverter can pull 166A with a charged battery, and it can exceed 200A on a weak battery, so 4/0 cable is a good idea.
12V systems really don't work well over 1500W but if prepared for it, it can work ok.
 

Leeds

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Lets start with the wire and breaker sizing for your solar panels. Can you specify the open and max power current and voltage on your panels?

Your 60A charge controller can easily deliver 768watts of power to your 12V system and with 600watts worth of panels you'll be just fine there.
But what isn't clear is how many volts your panels make when they are open circuit or how many amps they make at max power.

I suspect you'd be better off with two parallel sets of panels each parallel set consisting of three panels in series. All 6 in series is potentially possible too but you might enjoy the ability to have two banks on slightly different angles on your roof.

Once you show the data we can be sure but it appears as though you'll have only 5 or 10 amps flowing from your panels to the inverter on each of the two strings. Even 10 gauge wire would be overkill in this scenario...
 

Rocketman

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Were the new panels you purchased the exact same as the old panel?

When I say “exactly” I mean the labels on the back of the panels.

If not - post photo’s of the labels.
 
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