Hello, i have a new AC 200 PL and i was wondering about solar panels. The guide says max 15A - 1200W . does this means each panel can be max 15 A or max 15 A for al 2 or 3 panels
The device will not take more than 15A from the total amount of panels.
Because panels hardly deliver the maximum amps, you can exceed this 15A theoretical panel current.
There is no risk for the device as it will take no more than 15A.
You can damage the device if the incoming voltage from the panels is more than 145VDC.
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I would also like to reiterate what Bikerwally said. Its okay to exceed the amps but NEVER okay to exceed the max rated input voltage. Too high of a voltage can damage the charge controller, too high amps will just be wasted power.
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With Bluetti units that have a smaller cap on amperage, you’ll almost always want to combine solar panels in series to maximize production. When you combine panels in series, the voltages combine, but the amperage stays the same. On some Bluetti units, I believe if the voltage is below 32V, it limits amps to around 8-8.5A. By combining panels in series, you maximize the voltage potential to stay above that threshold, giving you more power.
There is a drawback to series, which is shading. Since the amperage remains the same across all the panels, if even one panel is shaded, it kills amperage for all the other panels as well. Most solar panels have “bypass” diodes in the panel, which allow current to flow around the shaded section. On many consumer panels, you’ll often see around three bypass diodes, which means every time a bypass diode is activated, you lose about 1/3rd of the panel’s amperage.
Current is amperage, so if you lose 1/3rd of the amperage, it’s spread across the whole system, not just one panel. For example, if you have four 250-watt panels in series, each producing 25V/10A, that would give you a total output of 100V/10A, or 1000 watts. If just a little bit of sunlight shades 1/3rd of the first panel, activating the first bypass diode (assuming each panel has 3 bypass diodes), the current drops to 6.7A, and the total output would be around 100VX6.7A or 670 watts.
What this essentially means is that the more panels you have in series, the larger your surface area, and thus the more you want to ensure none of the array is shaded, as shading will drastically reduce the output. If you’re planning to roof-mount solar panels on your camper, you need to make sure that nothing nearby causes shading, such as a Maxxair fan, A/C vent, or anything else. Depending on how big your RV is, you may or may not be able to tilt the panels.
The problem with tilting panels is that they cast a shadow, and since shading kills the array, you need ample space. Laid flat, they do not produce as much, but you can fit more panels on the roof. For example, maybe you can only tilt two 250-watt panels, but you could fit four 250-watt panels laid flat. While four flat panels would only give you 50% of the power output, that’s still the same as two 250-watt panels at full strength. During the summer months, when the angle of the Sun is higher, your potential would be greater.
None of this matters, though, if you mount the solar panels right next to your roof rack bar or A/C vent, and it shades 1/3rd of a panel. In that case, shading can kill 1/3rd of the overall current, drastically reducing the array’s performance.
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