Nope, nothing incorrect about that thinking. I’ve gone the same way, except I’m using twelve 250 watt (used) panels instead, for a maximum of 3,000 watts. You’ll have about 3,200 watts total.
I’m using the two separate arrays strategy, but it would seem that the parallel function would allow a single cable pair to be used instead, as you stated.
I’m using a 3s3p array of 320w panels using a single cable and then splitting it at the ac300.
I got an answer from Bluetti to my question about parallel mode. My question was:
The answer I got was:
Generally speaking, you do not need to turn the PV parallel mode on. You can refer to the diagram below to see when it needs to be turned on.
You only need to focus on the open circuit voltage. If the current or the power exceeds the maximum limitation of the unit, the unit will limit it on it.
The diagram shows PV from a generalized array coming in on two cable pairs, and neither the text nor the diagram suggests any distinction between the two cable pairs. Since having all the power on one pair would be a special case of that, presumably that would be allowed.
It also suggests that 12/24 amps and 1200/2400 watts are independent hard limits. I had been wondering, for example:
- Would 23A at 120V producing 2760W work because it satisfies the amp limit even though it’s over 2400W?
- Would 26A at 85V for 2210W work because it satisfies the watt limit even though it’s over 24A?
I’ve seen several reports of people getting power higher than 1200W per channel when not in parallel mode, which suggests that 1200 itself isn’t a strict limit, although there may be a strict limit at some value a little higher.
This is probably worth a separate post since it’s starting to diverge from the OP’s original question.
Interesting answer, and confirms what I thought would be the most likely answer. How I think it works is that each of the MPPT controllers will only take 12 amps, so to use anything higher than that a solar array needs to be connected to both MC4 pairs, which then gives a maximum of 24 amps combined. However, the way MPPT controllers work is to vary the intake current and see what level provides the best combination of voltage and amps, so to put a single array on two controllers would result in the two controllers fighting each other to find the max power. So, when the parallel mode is turned on I think Bluetti is making the two controllers work together at the same time in a cooperative mode, and that is what allows a single higher-powered array to work.
I personally have seen each of my controllers take in up to 1220 watts. Supposedly the max input, either via two arrays or one large array, would be 2440 watts. I’ll find out once I have everything installed.
This is good information, thanks for asking the question and sharing the answer.
some members here have stated that they can draw higher than 2400w per ac300 by using the parallel enabled. i am overpaneled with my set up. what’s the highest watts draw you’ve seen ? thanks
I’ve seen 2070, but perhaps not ideally optimized nor sufficiently overpanelled at that time. nominally that was with 2700 w possible going by the specs on the panels.
that’s almost 20 amps at my working voltage of 105 (calculated, not measured)
did you ever reach 2700 or you’re just calculating what it should be?
that’s just 9 panels x 300 watts. I only made it to 2070 , at least while I’ve been paying attention.
Thanks. I couldn’t find any docs on "PV Parallel. I was thinking exactly opposite, that when you connect 2 arrays (DC1 and DC2), it will parallel them internally or something, but that didn’t make sense.
It’s the little things…
That’s what I was thinking about the 24A limit. So that means I can only connect 2 of my 300 watt panels because each is 9.2 amps and that’s 1 allowed per input (12 amp max), but I bought 6 because it said 2400w max input per AC300 inverter. Ugh. I can’t get my batteries to charge as of yet. I was hooking up 6 panels in parralel. I need to figure this out. Any tips would be great. Bluetti hasn’t helped me yet and it’s been 8 months.
I don’t know what the open circuit voltage is on your panels, but you can string them in series up to 150v. that way the voltages add together but the amps remain the same, in your case 9 amps. for example, if the panels were 40v open circuit, you would string 3 in series and another 3 in series, then connect those two strings in parallel or just run them into the separate mppt inputs as separate arrays. you would get 120v at 9 amps for each string, at least theoretically. the mppt won’t set the voltage at 40 (probably closer to 35v per panel) and your amps will depend on the illumination/latitude/angle, etc but you could get 100v x 7 amps (700 watts)per string, or 1400watts for the two strings, set up that way
I get 2240W off my 10 PV200 whenever there’s a thin cloud layer overhead, in fact had it about 7 days in a row & I was concerned about it being that high but the folks on here said it was ok. But I was using both PV inputs on my AC300. It really charges the batteries fast! Without clouds my panels only produce 1.4 to 1.6kw. I have my fridge, freezer, & dishwasher hooked up 24 hrs a day to it to cut my utility bill & recoup some of what this cost me. It’s been saving me about $250 a month.