Installed two west side 12 panel strings, Aptos 440 DNA120 BF10, Voc 41.51v and Vmp 34.71v, and one east side 10 panel string (shorter roof). Time to mount the Growatt 11.4.
Ran string wires inside, checked voltage, and polarity. Noon local in north Texas, 50F outside - the right 12s measured 483v and the left 12s 484v. The 10s on the east side measured 405v. All three strings 10-15v below Voc while I was expecting close to Vmp. Am I getting a bifacial boost even though they are mounted close to the roof?
Coldest temp adds 16% to Voc, ~ 578v on the 12s. Still below a Growatt 11.4's 600v max but getting close and over the MPPT's max 550v. Are 12 440s too many? Could always turn off the 12s if we have a rare 0F period that adds a 20%+ increase.
Ran string wires inside, checked voltage, and polarity. Noon local in north Texas, 50F outside - the right 12s measured 483v and the left 12s 484v. The 10s on the east side measured 405v. All three strings 10-15v below Voc while I was expecting close to Vmp. Am I getting a bifacial boost even though they are mounted close to the roof?
Coldest temp adds 16% to Voc, ~ 578v on the 12s. Still below a Growatt 11.4's 600v max but getting close and over the MPPT's max 550v. Are 12 440s too many? Could always turn off the 12s if we have a rare 0F period that adds a 20%+ increase.