Solar install
My day has finally come! I've been piecing together a system over the last 6 mos and am ready to begin the install. I have 4 105ah agm wired in parallel, 2-210w Evergreen 12v panels and 2-145w DM...
Forum Discussion
big buford wrote:BFL13 wrote:
Are the 145s Mono? Poly example would be around 17.4 Vmp with two brands I know of
DM Solar
Sticker says 18.7 vmp, could be an error? I notice is says 18.0 vmp on sticker in photo on amazon ?
I thought I had a system where all poly 12v panels had similar specs/watt, but it's not that easy.
Rating- DM145w, Sharp130w, Sun 139w
Voc- 22.3, 21.9, 21.5
Isc- 8.37, 8.2, 8.74
Vmp- 18.7, 17.4, 17.4
Imp- 7.75, 7.5, 7.94
If you used the 145 with PWM you would get Isc for max amps. Compared with the 130 you should get 145/130 x 8.2 = 9.15 but it has 8.37a
the Sun 139 would get higher amps at high noon than the 145.
If you are using MPPT so Imp matters, then 145/130 x 7.5 =8.36 but it has 7.75
It is just math juggling, but it looks like that "145w" is getting killed on the amps side because the voltage component of the watts rating is way high.
There must be a an advantage why they chose to make them that way at the expense of the amps, but I know nothing about that--just trying to have a system that works for comparing panels and those DM145s are throwing my system off :(
