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PV array voltage too high?

Packen

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I have an Eg4 6500ex 48 with 2 mppts. Each has a max voltage of 500v.
My panels will be set up in 2 arrays, one facing east and one facing west. 12 panels in each array. My panels are 245watt and 37.7VOC.
If I run 12 in series it would be 452.4 volts per each mppt. Is that too much?
I don’t know how to factor in the voltage increase due to cold weather. It’s gets below zero sometimes. If the voltage gets above the 500v what would happen?
I was hoping not to parallel them to save using a combiner box and keeping the voltage up on the mppt.
Thanks
 
If you don't want to learn the math, use one of many online calculators

12 in series will likely be right at letting smoke out when it get at or below freezing, also that 500V is never exceed, operational is usually lower listed voltage, like 450 or such as shown for your inverter, meaning any voltage over 450 and the solar part won't produce energy
 
If you don't want to learn the math, use one of many online calculators

12 in series will likely be right at letting smoke out when it get at or below freezing, also that 500V is never exceed, operational is usually lower listed voltage, like 450 or such as shown for your inverter, meaning any voltage over 450 and the solar part won't produce energy
So I would probably be better off going with a 6S2P configuration for each mppt.
I was just trying to save a little money on two combiner boxes and wiring, but better safe than sorry.
Any suggestions on combiner boxes? Also looking for suggestions on affordable rapid shutdowns.
Thanks for your help
 
So I would probably be better off going with a 6S2P configuration for each mppt.
I was just trying to save a little money on two combiner boxes and wiring, but better safe than sorry.
Any suggestions on combiner boxes? Also looking for suggestions on affordable rapid shutdowns.
Thanks for your help
My arrays are 7S2P with 395 solar panels with a 500V limited inverter ( Solis 5G HVES ). I run home run from the roof to the inverter each string, no combiners as the inverter has connectors for each string so it is combined at the inverter ( two mppt channels, each mppt with two inputs ). Running a pair of 12 awg off the self PV wire can be lower cost that a single 10 awg as well, it is not as commonly used.
 
12 panels in each array. My panels are 245watt and 37.7VOC.
12x 37.7V = 452.4V at 25C

If you know your panel temp coefficient, it will make this calculation more accurate. I will estimate. .0035V/deg C

If the temp drops to 0C, that is a 25 deg swing:

452.4V x 25 x .0035 = 39.6V increase (492Voc, safe at this temp)

Do your MPPTs specify their MPPT (optimized voltage) range? I would configure the array (as suggested above) to stay within these bounds for increased efficiency. The suggestions to go 6S2P sound pretty good. And, for each MPPT, if you could put 6 facing east and 6 facing west, each MPPT will run at a much more gentle, cooler rate (6x 37 = 222V, hopefully well in the middle of your MPPT range).
 
My arrays are 7S2P with 395 solar panels with a 500V limited inverter ( Solis 5G HVES ). I run home run from the roof to the inverter each string, no combiners as the inverter has connectors for each string so it is combined at the inverter ( two mppt channels, each mppt with two inputs ). Running a pair of 12 awg off the self PV wire can be lower cost that a single 10 awg as well, it is not as commonly used.
I have a total of 24 panels, 12 on the east and 12 on the west so I would be running a set of 6S2P into each mppt, so I would need the combiner boxes, unless I am looking at something wrong. I don’t have my Eg4 yet due to back order but I did download the manual.
It would be nice not to have use the combiner boxes but I don’t think there is a way out.
 
12x 37.7V = 452.4V at 25C

If you know your panel temp coefficient, it will make this calculation more accurate. I will estimate. .0035V/deg C

If the temp drops to 0C, that is a 25 deg swing:

452.4V x 25 x .0035 = 39.6V increase (492Voc, safe at this temp)

Do your MPPTs specify their MPPT (optimized voltage) range? I would configure the array (as suggested above) to stay within these bounds for increased efficiency. The suggestions to go 6S2P sound pretty good. And, for each MPPT, if you could put 6 facing east and 6 facing west, each MPPT will run at a much more gentle, cooler rate (6x 37 = 222V, hopefully well in the middle of your MPPT range).
I figured on one of the calculators and I could go way over on really cold nights. Sometimes it get to -10F or below.
So you are saying I should use 6 panels from each side on each mppt?
 
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