Just watched a video on it to charge a Bluetti and/or Battery using an extra solar panel through this.
The B300s already has an input plus the cable to plug in extra solar panels DIRECTLY into the battery. You just have make sure the panels are within the 60 Voc input spec for the battery.
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I’ve been using all my spare panels after I set up some new arrays, plugged directly into 3 B300s batteries. I used a clamp ammeter to see that the batteries are indeed pulling power from the panels even while being charge through the AC500 head with it’s 2 arrays.
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It would seem more logical to spend that money on solar panels that you CAN plug in directly, unless you have money to burn, which if that’s the case I could use another AC500 head to start running 240V 
D050S is mainly used for PV charging of the B300S from solar panels via the adapter input of B300S.
So are you saying this is to add an ADDITIONAL 500 watt solar panel to the battery in the lower plug AFTER you already have a 500 watt panel connected directly to the battery in the upper plug with the supplied cable (whatever it’s called), for a total of 1000 watts solar?
Ok, that makes sense now.
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I was looking at those befacial 550 watt panels, but you still can’t get the 500 watt limit out of them because the battery input limit is 10 amps, and the panel voltage is 42V, so only 420 watts or less in the real world, likely in the 380 watt range.
The DO50S also allows additional solar input on the AC200 and AC200P models as well as allowing a single solar panel to charge when the solar output is less than 35 watts.
There’s not a whole lot of information about it on the website, or even in the downloadable manual. They could likely sell more if they eloborated on the description.
You can seen in various youtube commemts people needing more information about Bluetti products, that they can’t get from the website.
The B300 has two input ports, a DC and an adapter input port.
The DC port can directly connect to the solar panel, but the maximum input is only 200W.
The adapter input port is mainly used for adapter charging, the maximum input power is 500W, but this port needs D050S if you want to connect solar panel.
Hi there, Im just reading through this thread and have a question. I recently bought an AC200L, a B300 expansion battery, and a D050S charge enhancer. I was under the impression the charge enhancer would take my B300 expansion battery from 200W max PV to 700W (B300 max PV is 200W + the 500W from the D050S = 700W). I was told that is not the case. I was told that even with the D050S charge enhancer, the Max Solar, PV, input for the B300 is still only 200W. Is that not correct? Likewise, adding the charge enhancer to the AC200L would also NOT increase its charge capacity either. When I asked what the point was for the charge enhancer then, I was told it was necessary to have in order to charge the B300 via solar panels. Is this correct ir did I misunderstand something?
Jake
- Using the D050S, the PV charging power can be increased to 700W. The PV input port of the B300 is limited to 200W of power. Connecting the D050S to the 7909 input port of the B300, the 7909 port has a maximum power of 500W, so 700W can be achieved.
- Using the D050S to charge the AC200L will not increase its charging capability, that’s correct.
- To use a solar panel to charge the B300, you don’t necessarily need the D050S, because the B300 has an XT90 PV charging port. It’s just limited to 200W of charging power. The function of the D050S is to allow charging through the 7909 port as well.
The original purpose of the D50S what to enable an AC200/P unit to increase charging speed. While input through the PV port was occurring the AC charging brick input port could be utilized by the D050S as a second input port thus increasing charging wattage that was not available before. A secondary use was that a single smaller solar panel could be used to charge the same unit which has a 35 volt minimum requirement to begin charging. The D050S takes a lower input voltage and increases it to a higher voltage around 58 volt which is then output to a compatible device.
This is very helpful info. Your above description was my initial understanding of how the D050S worked in conjunction with the B300. I really appreciate the clarification on this matter. Thats a big jump in charging speed, going from 200W to 700W withe the enhancer! Im excited. Again, thanks for the clarification.
Jake
Thank you Scott for the info. Really glad that I found the Bluetti community! A lot of knowledgeable folks who are willing to share info and help us newbs. 
Jake
Another benefit for AC200 MAX users is that with the D050S charge enhancer, the user can charge from two separate solar arrays at the same time. For instance, I can charge my MAX while driving with the two CIGS panels that are installed on my truck cap’s roof. When stationary, I can charge the MAX from the CIGS panels AND from the PV200 panels setup in series - the CIGS panels are plugged into the D050S and the PV200 panels are plugged into the PV port.