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Post by so36idavid on Oct 14, 2017 14:44:00 GMT
So a good MPPT controller should be able to make use of the full power available from series connected panels, with the advantage that it would continue to feed some current to the battery into dusk, when even the series connection might output a total of less than 12 volts? So long as the maximum voltage is within the specifications for the unit of course. I presume the three stage algorithm is mostly about battery voltage and tapering off the charging current, but is it affected by other chargers such as the engine alternator operating at the same time? What happens then when one of the series connected panels is partly shaded? Does this just reduce the overall output voltage? Or does it cause a high resistance path through the shaded cells, which might lower the total current? Hi Rene, Yes, I get a small amount of power out of the panels well into dusk. If you put solar panels in series then a fully shaded cell is an open circuit, it will stop the current flow of the whole system. If a cell is partially shaded then you'll get something out of the system but not much. Some of the higher end solar panels mitigate this by wiring up multiple strings of cells in parallel in a single panel. So if part of the panel is shaded you'll still get power out of the strings that are not shaded. David
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Post by vasko on Oct 14, 2017 15:24:44 GMT
battery monitor measures the actual result of in-out from the battery bank - e.g. to actually see what the panels can produce you need a discharged battery bank ( to make sure that the bank can consume the full power of the genersted from the panels) and switch all consumers off and then look at the monitor - e.g. you need to prepare especially to measure , mesure and get back to normal that is why I have my own advance hand made battery monitoring system - currently in testing - other option is the cotroller to show the numbers ...
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Post by so36idavid on Oct 14, 2017 18:16:15 GMT
battery monitor measures the actual result of in-out from the battery bank Agreed, I thought that's what you were asking . I don't know what the panels are capable of producing, all I know is what I've actually seen in the real world. I don't discharge my batteries below 50% so I don't know what the panels are capable of. The most I've seen coming out of them is 170W. I have two rated at 120W each so I'm quite satisfied. I'm sure I could get more if they were appropriately tilted etc. but I don't need that. David
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Post by vasko on Oct 14, 2017 20:38:44 GMT
That sounds about right .... from 240W you should get about 12-14amps in very good conditions e.g. - 144-168W max...
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Post by vasko on Oct 14, 2017 20:43:50 GMT
btw: re battery maximum charge current - up-to 70% of th charge the wet/gel/agm batteries can accept about 30% of the capacity e.g. if you have 400ah bank it can accept max 120amps charging current - e.g if you have seem max 170W when batteries at 50% then you have seen the max output of the panels...
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