I have a 24-volt Growatt that I am replacing once the Eg4 6500 comes back in stock. But until then I want to connect an additional 4 250-watt solar panels to my existing 1200-watt (6x200) panels.
Here's the issue. The 250-watt panels are 37.4 VOC 8.3 Amps, and the 200-watt panels are 22.6 VOC 11.2 amps. The only way I see this working is 2s2p the 250 watts and get 74.4 Volts at 8.3 amps. Then 3s2p 200-watt panels at 67.8 volts at 22.4 amps. series both arrays together and that would leave about 135.6 volts (because it is the lowest voltage x2) and the amps should be 30 I believe. (All are used panels of about 5 years.)
2S2P 74.4 volts at 8.3 amps series to 67.8 volts at 22.4 amps = 135.6 volts at 30 amps. on 10 gauge solar wire 70 ft.
I plan on using a one-way diode on each positive series.
First is my math right, second is this safe? and third is there a better way of wiring them, or am I forced to use a second solar controller?
I would love to run the 4 250 panels all in series but that is 149.6 volts. and the Growatt is max PV input of 145 volts
Thanks for any help.
Here's the issue. The 250-watt panels are 37.4 VOC 8.3 Amps, and the 200-watt panels are 22.6 VOC 11.2 amps. The only way I see this working is 2s2p the 250 watts and get 74.4 Volts at 8.3 amps. Then 3s2p 200-watt panels at 67.8 volts at 22.4 amps. series both arrays together and that would leave about 135.6 volts (because it is the lowest voltage x2) and the amps should be 30 I believe. (All are used panels of about 5 years.)
2S2P 74.4 volts at 8.3 amps series to 67.8 volts at 22.4 amps = 135.6 volts at 30 amps. on 10 gauge solar wire 70 ft.
I plan on using a one-way diode on each positive series.
First is my math right, second is this safe? and third is there a better way of wiring them, or am I forced to use a second solar controller?
I would love to run the 4 250 panels all in series but that is 149.6 volts. and the Growatt is max PV input of 145 volts
Thanks for any help.