I have an AC 180 and i was wondering is it safe to connect 3 200watt solar panels in series to my AC180?
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That’s a definite maybe. To answer that question we basically need one piece of information from those panels, the open circuit voltage (Voc). FYI, the output voltage of solar panels CAN go higher than the rated Voc in very cold conditions, so keep that in mind. The max power current rating would be useful information as well, especially to see what solar input might be expected.
The AC180’s solar input information from the manual is 500W Max., VOC 12-60VDC, 10A. The primary information when determining what solar panels to use is the VOC rating, which is listed as 12 volts to 60 volts DC. From that we know that the minimum maximum power voltage (Vmp) to charge at all is 12 volts. But the maximum allowed for the open circuit voltage (Voc) is 60 volts. Note that this is for the Voc, not Vmp (maximum power voltage, which is lower than the open circuit voltage). Also note that we don’t fully care about the current rating if it’s higher than the 10 amps, nor do we care if the wattage is higher than the 500 watts. The AC180’s charge controller will manage the current and watts. However, it cannot regulate the voltage from the panels, so if the Voc is too high it will damage the AC180.
So if you can put the panels in either all series, or all parallel, and keep inside the 60 volts, then it should work. If you could let us know the Voc of the panels we can verify!
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Thanks for your response. 23.7, 23.7, 26.1 voc. Is it possible to put a voltage regulator in line to keep voltage down to 60 volts? I am trying to achieve max charging while using the generator to power equipment.
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The total Voc you have is over 70V. I would suggest this is dangerously high. I only use 2 panels in series on my AC180 to be safe. They are only 150W each so I am only able to achieve a max W of 300 and usually less. I don’t want to spend the extra $$$ on new panels, so I came up with another option as I already have the equipment. Using a Victron 375W inverter wired to my 4x4 and using the Silent mode 240VAC charge setting, I get around 280W from AC and at the same time around 250W from solar. This gives a total of over 500W, but I need to idle the car. If driving I have a 110W on roof panel which usually gives 90W and the inverter the 280W for a total of 370W or so. I look at it from the perspective of having more than one option to charge when off grid. Probably not what you want to do, but my method may give you some alternate ideas. 
Thanks. Why would the AC180 be rated for 500 wats and yet there is no way of achieving it?
A 48v LifePO4 battery (or four 12v in series) plugged into the DC input port will give you 500w so the maximum wattage is achievable but would be difficult with solar panels due to their VOC.
That is what i am looking into. Thanks
The AC180 solar input specs are 12 to 60 volts - 10A max at 500W. First point, the critical limit of the MPPT controller is voltage maximum. Exceeding this may damage the electronics. Second point, amps are limited to 10A, however if your feed in is slightly higher, the unit will still limit input to 10A. Third, similarly, watts at 500 can be somewhat exceeded, I don’t know by how much, but I have a caravan MPPT that is limited to 50V and 30A. The specs don’t note Watts. However, the manufacturer has told me 600W max, but can accept up to 800W providing the voltage is within range. Next post to you… with more. :)
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Most 12V solar panels have an open circuit voltage of a bit under 20V for cheapies and between 22-24Voc for better quality panels. Two panels in series will calculate to around 48Voc. A 180W panel roughly calculates to around 10A short circuit voltage, a 200W panel 10-12A short circuit amps (Isc). As the AC180 limits to 10A, multiply 10A x 48V = approx 480W. The first thing to note is using bigger than 200W will still be current limited to 10A, however when output is lowered by conditions, the extra output of say a 250W panel will take up some of the slack. WARNING - if you try to connect 3 panels in series the Voc will be over 70V and probably damage the AC180. Hope this helps. :)
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