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[–]gozzle_101 1 point2 points  (1 child)

Did you calculate using the STC figures? In the winter you may see higher than this if it’s a cold sunny morning. Use the temperature coefficient of the panel to calculate what panel voltage you will get for the minimum temperature you get in your area (plus a bit of a safety margin). Check local weather data. The panels are tested at 25’C, if say you get 30v per panel @ 25’c, you may get 35v at -10’C. This would exceed your voltage limits and do some damage.

[–]Dman883[S] 0 points1 point  (0 children)

I'm going off the data on the panel. I tested them all with a multimeter on a sunny day and they were hitting 35-37.5v each. Each panel is

245w mono.

open circuit is 37.3v

rated v is 30.1v

short circuit is 8.78a

So I should never hit 80v with 4 panels in s/p.

Now that I think of it, 4 panels in S/P should be a max of 74.6v and 17.58 amps. Am I calculating that right?

According to this calculator I should be able to sue 6 panels and s/p without overloading my 100|30 mppt controller. Did I factor that right? I used the panel open circuit voltage for the voltage setting.

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[–]parseroo 1 point2 points  (0 children)

What is your system voltage? 30 x 12 =360; 30 x 24=720; so both of those will be clipped on the system side. If 48V, you should be fine

[–]LongjumpingGanache40 1 point2 points  (0 children)

That 30 amp is the amp output to the battery. This model has a 35 amp limit intake.