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wire gauge for two 12V LiFePO batteries connect

jetjaguar

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Hi Team,

What gauge wire should I use to connect the two batteries together in parallel?

My stuff:

Batteries: two 12V, 100Ah SOK LiFePO batteries in parallel.
Inverter: Renogy 1000W Pure Sine Wave Inverter 12V DC to 120V AC
Panels: 200W of solar panels
Charge Controller: MPPT 75V 15A 12/24V solar charge controller.
 
What gauge wire should I use to connect the two batteries together in parallel?
A 12volt 200 Watt inverter will draw 16 Amps. 20 guage wire would be the minimum with a 20 Amp Fuze to protect the wire. That should work for charge controller unless the distance is long.
NOTE: Thanks to @rmaddy the correct inverter size is 1000 Watts, See his post below for the correct wire guage.
 
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A 12volt 200 Watt inverter will draw 16 Amps. 20 guage wire would be the minimum with a 20 Amp Fuze to protect the wire. That should work for charge controller unless the distance is long.
The OP has a 1000W inverter and 200W of solar panels.

A 12V 1000W inverter can pull up to 100A from the batteries. This means you need at least 4AWG but 2AWG would be much better. Use the 2AWG to connect the batteries in parallel and to the inverter. You will want a 125A fuse between the batteries and inverter, very close to the batteries.
 
The OP has a 1000W inverter and 200W of solar panels.

A 12V 1000W inverter can pull up to 100A from the batteries. This means you need at least 4AWG but 2AWG would be much better. Use the 2AWG to connect the batteries in parallel and to the inverter. You will want a 125A fuse between the batteries and inverter, very close to the batteries.
Those batteries in parallel add up to 200a. Does that matter in this computation of wire size and inverter size, or do we just consider the amps being pulled by the inverter?
 
Those batteries in parallel add up to 200a. Does that matter in this computation of wire size and inverter size?
It's the loads that determine the wire size and the loads are determined by the inverter size. The combined max continuous discharge current of the battery bank needs to be high enough to meet the loads. In this case the loads are 100A. So a single battery can run the inverter. Having the 2nd battery isn't needed just to meet the loads but it does of course increase capacity which means more runtime. In this case it also means that if one battery fails for some reason, the other battery is still capable of carrying on running the full loads.

If the OP wanted a 3kW inverter which means loads up to 300A then the two batteries wouldn't be enough. So knowing you only have 200A of discharge current does limit the max size of the inverter that could be supported, which would be 2kW in this case. This all assumes a 12V system.
 
The OP has a 1000W inverter and 200W of solar panels.

A 12V 1000W inverter can pull up to 100A from the batteries. This means you need at least 4AWG but 2AWG would be much better. Use the 2AWG to connect the batteries in parallel and to the inverter. You will want a 125A fuse between the batteries and inverter, very close to the batteries.
This is great information, thank you. I thought I would need a much heavier gauge wire for that part, as shown in the videos. I will purchase a good crimping tool and save my gold to buy some copper. haha.

Is Amazon the best place to purchase supplies like 2 AWG wire? I mostly shop there, but I am open to suggestions on the matter.
 
Is Amazon the best place to purchase supplies like 2 AWG wire?
The trick is ensure you get actual pure copper (possibly tinned) stranded wire. Avoid copper clad aluminum. Some places will claim pure copper but sell copper clad aluminum.
 
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