I am having following solar system installed in our home by the reputable solar installar listed on the SolarQuotes.
- 10kW Fronious Symo inverter
- 31 x Qcell QMaxx 390W panel (20 panels on north facing roof, 11 panels on south facing roof)
- System size and orientation is not an issue. Due to the limitation with our roof this is the only option.
- No shading issues
The installation is partially completed and due to be completed on comming Monday.
While reading the documentation left (Your PV Systme Details) by the installer, i found following:
- MPPT/Input 1: 11 Panels x 2 String
- MPPT/Input 2: 9 Panels x 1 String
Now, my question is, after reading few articles on google on those solar installation sites, i was under the impression that the solar panels with the same orientation are usually groupped (or Stringed) together, unless this is not physically possible. As we are installing 20 Panels on North facing roof and 11 panels on South facing roof, i was under the impression that the strings would be configured following:
- MPPT/Input 1: 10 Panels x 2 String
- MPPT/Input 2: 11 Panels x 1 String
However, based on the configuration shown on the installers document, there will be 2 Strings of 11 Panels which means the panels with the South and North orentation will be on the same String. Google search suggests that this may cause performance issues.
I have asked this question to the solar installer through email, but as its weekend i do not think i will get the answer by Monday. And as the installers are comming back on Monday, i would not have much time to discuss about this issue. So i was wondering if anyone knows if this configuration is normal, or if i should contact them first thing in the monring on Monday, to have the String configuration changed.
The installer responded that the configruation is:
- MPPT/Input 1: 11 Panels x 2 String (11 South Panels and 11 North Panels)
- MPPT/Input 2: 9 Panels x 1 String (9 North Panels)
They also commented that 10 + 10 north panels would have been easier for the installers. But 11 + 11 wouldn't impact the efficiency of the north panels as both north and south strings are seperate string. It doesnt really make sense to me… Is this correct?
I asked for an independent professional review of the proposed String arrangements. Then the installer agreed to install the panels 10 + 10 North and 11 South. Installation is now complete.
Thanks for your input guys.