Advice on my ac200max set up

I need advice on my setup plz. Im 75 yrs old started this project about 6 months ago. Decent with 120v,240v, no solar exp.Have 7 300w solar panels on my garage roof.I bought 7 because i thought I read that a blu AC 200 max could take 2100w. 300wx7=2100w. 7 panels grounded to rack,grounded to earth. 10 ga. Copper stranded 125 feet to cutoff switch on outside of house. Through wall and into my ac200max +2 b230s. 10 circuit Reliance transfer switch wired into my grid panel per instructions.Plan to hook panels (OCV=45v) ( SCC=8.74) 3p series=135 v,3p series=135v. 2 strings parallel =17.4a total = 135 volts /17.4 amps =2349 watts
Does this look correct? Is there a way to use 7th panel? Do I need to fuse anywhere? Am I too much overpaneled ?
Panels are used and I will have some shading at times. Never posted on a forum hope this works. Wife keeps asking when we going solar !!Get off that roof ! Happy wife happy life. Thank yall for any help.

Hello, welcome to the community. I have an AC200max as well. It looks like you are a little over on the panels because of the amps. The MPPT on the ac200max is only rated for 15 amps. What you could to is: save the extra panels for if/when one of your panels in use gets damaged, get a charging enhancer (DC Charging Enhancer (D050S)), get a step down (PV VOLTAGE STEP DOWN MODULE(D300S)) which the ac200max user manual SAYS is an optional accessory for the ac200max.

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The AC 200 is only rated for 900 watts input from solar, you can over panel a small amount due to shading and cloudy days etc depending on where you live. If you’re in the sun belt you could probably get by with 1000w of solar. If your slightly over paneled the current will be limited and you won’t charge to much past 900watts. you are way over paneled, to the point where you should buy a larger system or sell off some panels.

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Need assistance with my AC 200 Max not holding a 100% charge over night. During 28 deg temps my 200 MAX 100% charge drops to 70% by morning. AC/DC output is off. Any advis?

I agree a little over on amps but I have read dont worry so much about amps because the 200max will only pull 15 amp’s …Do you agree? DC charging Enhancer would let me cram 1400 watts into the max right? Now 2349 total watts of output presently at 100% . Effective rate is 80% of that is 1879 W…Used panels (-10% ??) 1691 watts //If Im correct on numbers and math I can add a DC enhancer and be slightly overpaneled… How is that for a new plan ?? Doyou have any suggestions forf optmizing my 7 panels in another configuration ? Thank you for answering

I would say turn it off overnight. If you have PV coming in, it will turn back on as soon as the panels are energized. You can power it off via the mobile app…too bad there isn’t a setting that will turn the unit off as soon as the PV input drops to 0 if both AC and DC outputs are off.

I cannot speak to that. I keep my input below 15 amps. I do know you can over-panel (exceed the rated input), but I can never remember if it’s amps or volts that you DO NOT want to exceed. You could either go with whatever Bluetti recommends or try going over (17.4 amps) and see if it gives you a fault code. I don’t know if going over on amps would void the warranty. With the DC charge enhancer you will be able to input 1400 watts via PV. That would use 5 of your panels. The way I look at using solar is that you can store power (battery) and you can make power (panel potential). The less you can make in one day the more you will have to store. The less you can store the more you will have to make in one day. There is a balance. You will have a given need/want based on how you use power. Another thing you could do (involves spending more money) is buy a B300 battery (which has it’s own MPPT), you would have more storage and you would be able to use one more panel on the B300.

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First this started out to be a “TSHTF” project. Then as I spent more money I thought I should get some return on investment by running solar 24/7 on most of my 110 volt circuits thus the 10 line xfr switch…So any power I make will be less power I get from the grid …From what Ive read on forums Volts is the one you DONT go over. I will order the charge enhancer tonite…On the b300, do you mean run a b300 as a stand-alone unit? Is that possible? As you can probably see Im pretty new to this although I think I have watched every utube video on solar and have everything hooked up but the panels so I REAlly appreciate your help. I dont mind spending more $ as long as it makes my setup more efficient/viable…Thank you again

I hear you on the SHTF… That’s why I bought mine and it morphed into using it all the time… The B300 can be added to the AC200Max (you’re capacity with AC200max and B300 would be around 5kw). Also the B300 has it’s own MPPT (you can charge the B300 directly from a solar panel) and it has it’s own DC output. Yes you can use the B300 on it’s own (which I think is kinda cool). If you ran the B300 as a stand alone you would be limited to DC (12v plug, power delivery port, and USB port).

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look here
I too had the problem. a bms update is the solution. but it will be activated upon request.

I have older firmware on my ac200max. It’s been working flawlessly so I’m gonna stick with it (no upgrade) until there is a problem. I use it daily…probably running running .7-1.7kw through it a day.

“you can over panel a small amount due to shading and cloudy days etc depending on where you live”
Bluetti has stated officially that significant overpaneling is allowed (not just a little) on the maximum power front (more current capacity). Although only 900W will be used max, more can certainly be connected AS LONG AS input voltage limits are not exceeded.


There is no problem with being overpaneld. You can have as many Panels as you want as long as the VOC is below 145V

this is correct.