I am experimenting how solar works with an Elite 200 V2 connected to an EcoFlow 160W portable panel, both recently bought brand new. The max input achievable has dropped from c140W to c45W and I am currently working through ticket 468183 to try and resolve this issue. Their custom firmware updates haven’t helped.
I would like to understand if/how/why the Bluetti unit controls the input current. The panel seems to be working fine with a measured Voc of 20.9, close to the quoted figure of 21.3V. Max Isc is quoted as 9.1A. Is it possible that the unit is somehow restricting the input current?
I have also seen reference with faulty MPPT boards: is this more likely?
There are a number of reasons for variable charge rate and as you don’t mention details, I’ll list them;
Voltage plays a big part - One panel at a Voc of 20.9 will place input in the restricted input Amps category. Below 30V input, my smaller power stations are limited to 8A when the maximum is 10A. I believe this to also be the case with my Elite 100 v2 which has a max amps DC input of 20A, the same as the Elite 200. To get maximum amps you need a nominal 24V panel or 2 nominal 12V panels in Series to double Voc to around 42V.
SOC of the power station - If a power station is at 100% or near to it it is full and the MPPT will cut or lower input, regardless of panel output. Firmware updates won’t change this, it’s battery science 101.
As an example - Brand of panel is not as important as how you use them. I have 2 x 150W Hardkorr solar Mats and 2 x 160W Dune Panels. Both arrays are approx 20Voc and 8-9A Imp. Each array (brand) is connected in Series for an Approx 40Voc and 8A+ Imp. Both Series Arrays are then connected together in Parallel for 40Voc and approx 17A Imp. This maximises output to a total of 620W theoretical output, however, on a really good day, output has never exceeded 500W due to environmental factors such as temperature, haze etc and panel position as the sun moves.
As a possible check - make sure your E200 is around 50% SOC so solar will work, connect the panel to it. Then with a multimeter check the panel voltage near the input to the E200. A better way is make up a small lead, and get a DC power meter inline near the E200 input to check both volts and amps to see if the panel is actually producing and at what rate. i.e. it could be the panel under load or indeed the cable between panel and power station. I have had a similar issue and it was one MC4 connector pin issue and a power meter is the only certain way of knowing.
Perhaps you could switch to advanced mode to try and fix the 8A current limitation issue for voltages below 16V. However, the significant power drop from 140W to 45W suggests there must be another problem. But it’s worth a try anyway; it might work.
Thank you for responding. I checked the panel again and the full sun output is 20.9V but only 2.8A so I suspect the problem is the panel; still waiting to hear back from the manufacturer.
Thank you for taking the time to respond. The battery SOC was c20%. I changed the cables back to the one supplied by Bluetti and checked the panel again with a multimeter. The measured (full sun) output is 20.9V but only 2.8A so I suspect the problem IS the panel; still waiting to hear back from the manufacturer. I don’t know why I didn’t check the output current first time round!
What you did was essentially a “short circuit current” test. What the panel could theoretically produce at a maximum under zero resistance. The parameters change when you introduce a load because the IV curve changes, then the MPPT controller settles on its “maximum power point” (AKA “MPPT”). The other side of the coin is interpreting the data. You said full sun, BUT what time of day? Was the panel flat or was it tilted and aligned EXACTLY to the Sun with the trusty soup can test (or an analog solar alignment tool). For example if you did the test in “Full sun” but it was laid flat and done at 9AM in the morning, it would read 2.8A possibly. Not saying that is the case, but context is important. Signs definitely pointing to the panel because at 20% SOC it should be charging higher than 50W under full sun.
It is a rare event for us here in North Wales but we have just had a spell of high pressure with cloudless skies. I measured the output over three hours from 11.30 to 14.30 and moved the panel to track the sun. I used the ‘solar tracker’ incorporated into the panel to try and achieve the optimal angle. Seriously I couldn’t do any more to help out the panel and the Bluetti but the input wattage stayed at c. 47W over the whole period. SOC increased from 17% to only 23% over the three hours. I periodically, and carefully, disconnected the panel and continued to measure approx 20.9V and 2.8A.
Are you saying that the readings would have been different if I had connected a load to the Bluetti?
Are you saying that the readings would have been different if I had connected a load to the Bluetti?
Not drastically different from the open circuit reading, similar to what the actual output is, minus a few due to resistance. Think of it like your car has a MAX speed but realistically you can only make it SO fast down a stretch of road before you hit a stop sign, or a curve. The short circuit current test you measured it just theortically the “fastest” your car can go with an open road (no curves, no obstacles) in that condition. Since it was sunny out, your panel was not laid flat, and you are in North Wales at this time of the year its fairly obvious your panel should be outputting more than 45W. It is experiencing high resistance (internal wiring fault, bad soldering, bad junction box, loose/bad MC4 connection) which explains the low current draw, but perfectly normal voltage. You can try replacing the MC4 connectors at the base of the solar panel if thats viable, otherwise, time for warranty.
@davidcourt No prob, it’s something very commonly done. When you have an “assembly of components”, it’s easy to point the finger at only one. Fault finding is a process and “each part” of that assembly needs to be considered and checked. To explain;
The solar panel.
The cable from the panel to the Bluetti solar input cable.
The Bluetti solar cable to power station
The Power Station.
State of Charge of the battery, if it’s full input will be zero.
Amount of Sun
Anything else not mentioned, i.e. power station internal electronics, connectors etc.
Each of these are points of failure and a multi meter is essential to check most of those parts. A clamp ameter or inline power monitor is better, lol.
Keeping it simple, check SOC (the easiest to do), then cables (also easy), then panel output, (open circuit, under load and a little more effort), then finally the most intricate is the power station.
Other options are to swap out cables, panels and a different power station. This requires spares or the ability to make up cables etc.
Your analysis seems relevant; the problem could be with the panels. I note that the power you’re getting is roughly a third of the power and current you should be getting. I also see that your portable solar panel is made up of three sub-panels :
Is it possible that the three sub-panels are connected in parallel, and that the connection of two of the sub-panels to the outgoing MC4 cable is broken? This would mean you’re only getting the power of one of the three sub-panels ? To test this, you can do a simple experiment: place your panel in full sun, cover two of the three sub-panels, and leave one sub-panel exposed to full sun (there are three possible covering combinations). If, with one of the covering combinations, you get your maximum current of 2.8A, there’s a good chance the electrical connection to the two covered sub-panels is broken somewhere.
Thank you again. Yes I have done the ‘cover/uncover’ test and found that only one of the three panels (the rhs one with the connectors) is working. Ecoflow have now accepted that the fault is with the panel rather than the Bluetti unit, fingers crossed they will not be slow in sorting out a replacement for me. All part of the learning experience, I should have spotted straight away the ‘one-third power = two dud units’ equation. I wonder if this is a common problem with folding panels?
Glad to hear that Ecoflow is going to send you a new portable panel. I do think that folding panels are more fragile than rigid ones. In the case of the Ecoflow panel, you do need to connect the two terminals of the sub-panel furthest from the MC4 connectors to the wiring of the central sub-panel, which is itself connected to the wiring of the sub-panel with the MC4 connectors. I think that since the cables have to pass from one sub-panel to the other, they must be bending at the joint between the two sub-panels when you close them. If that’s the case, good news! If you’re handy, just check the joint between the central sub-panel and the sub-panel with the MC4 connectors for a broken electrical wire: resolder it and you’ll have a second portable panel!
