AC200Max with 2S2P 360w Solar, what AWG cables?

I’ve been trying to figure out what AWG cable I should be using throughout my set up.

Currently I received my AC200Max a few days ago and everything has been great. I’ve discharged it to 0, and charged back to 100% to get it ready.

I’m waiting for a few supplies to come in before I hook up my solar panels to them.

I plan to have 4x 360W panels in a 2s2p configuration to allow for the Voc to be lower than the 150W limit. If I connect 3x in series (this would be optimal setup), it would hover around 135V which could potentially spike above the 150V limit in the winter.

Here is the stats on the panel:

in 2s2p configuration, I pop into footprinthero calculator I get the following that will be overpanelled in W and A for the AC200Max (900W and 15A), which I’m okay with.


The question is, what AWG cable should I be using? The cable run will be around 30 ft to the AC200Max. I was thinking 10 AWG (which I can reuse again later if I move the AC200M to a further location, making the run longer) but noticed that the included Bluetti XT90 adapter to MC4 is only 14 AWG, so would this be an issue that the cable adapter is too thin to handle my configuration?

Panels connected via 10 AWG 30’ cables connect into 14 AWG MC4>XT90 adapter to AC200M.

Any help from the community would be greatly appreciated!
Thank you in advance.

In my home country nobody uses PV cable less than 4 mm²/12AWG, or if you want to avoid cable losses, I would recomend 6mm²/10AWG.
I used 12 AWG on each single module for connecting to micro inverter (around 15 ft), and 10AWG for connecting two modules in parralel to micro inverter.

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Thank you! I figured, I am having a hard time finding any sort of XT90>MC4 cable that is at least 12 AWG.

This is how my setup will be wired up, maybe I should be using 12 AWG for the long 30 ft run instead of 10 AWG for now. In the future, I intend to move the power station downstairs into the basement once I get a sub panel/transfer switch installed and then need the solar to run further (probably 50 ft). The 16 AWG to XT90 is okay for this short run into the AC200M?

Why do you want to using 12AWG instead of 10AWG? 12WG would not be wrong, but note that the smaller the AWG, the thicker the wire. 10AWG is thicker than 12AWG and would be better for longer distance, you will lose less power …

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Your bluetti xt90 to MC4 cable should be 14 awg, it is on mine, it is that way on my max and also on my ac200p. It is a 14 awg (80 degree C) which is rated to safely handle 22 amps.

12 AWG copper wire is more than sufficient if you are running under 20 amps. 10 awg over 30 ft will reduce voltage loss by about 1%.

Voltage loss with your metrics with 12 awg over 30 ft = 2.68%
VS 10 awg = 1.61% loss. Those #’s are from using your setup’s volts & amps on the southwire calculator.


I was having difficulties trying to find an XT90>MC4 connector at 10 AWG.

However, I did find XT60>MC4 10 AWG and a XT60>XT90 adapter, which will work well.

The 32A fuse box already has cables attached (12 AWG) which is now my bottleneck, Im reading that with a 2S2P setup, a fuse box is really optional. I might take it out of the setup.

I would turn off the fuse to do work on the panels itself, but it wont be needed to protect a panel short, as theres only 2x panels in series, if one of the panels have a short, it wont feed it back to the other panel to cause overvoltage. Only needed to protect if 3+ in series.

Thank you for the calculations, I’m leaning towards using 10 AWG throughout, I’ll take out the fuse box (12 AWG cables already attached) and upgrade the XT90 cable to AWG.

This will minimize my voltage loss, even at further distances once I move the AC200M to its final location (eventually!).

Regarding a XT90 - MC4, i purchased a 50 ft, 10 awg wire yesterday on eBay. It will connect to the aviation cable - xt90 and run directly to my 2S3P roof mounted panels. I’m going to add a screen shot of the wire I bought, in case you’re interested.

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Thank you to everyone that assisted with calculations and advice.

I already bought most of my cables so I’ll just reuse those. But I did find a XT60 10 AWG cable and used an XT60-XT90 adapter instead.

Everything is working great, I hooked up 3 panels and been getting the max solar production for my testing purposes.

Now I need more load to make use of my new found solar.

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Very nice. I see my wattage briefly bounce around in the high 900’s but it settles into 920 - 925 peak power. I have a 200 watt panel connected to my b300 as well, but the max doesn’t display that watt value. Finding ways to use the power can sometimes be difficult.

I have plenty of load within the house, the problem is connecting the battery to it. :slight_smile:

Eventually I’ll want to upgrade the battery capacity and want to hook it up via a subpanel/transfer switch to provide power to sockets/leds but trying to finalize my setup first before I go deeper into this project.

I too want to setup a transfer switch with mine. I currently power the master bedroom with my setup. That typically makes full use of my solar power.

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