Solar panel wiring (also known as stringing), and how to string solar panels together, is a fundamental topic for any solar installer. It’s important to understand how different stringing configurations impact the voltage, current, and power of a solar array so you can select an appropriate inverter for the array and make sure that the system will function effectively.
The stakes are high. If the voltage of your array exceeds the inverter’s maximum, production will be limited by what the inverter can output (and the inverter’s lifetime may be reduced). If the array voltage is too low for the inverter you’ve chosen, the system will also underproduce because the inverter will not operate until its “start voltage” has been reached. This can also happen if you fail to account for how shade will affect system voltage throughout the day.
Thankfully, modern solar software can manage this complexity for you. For instance, Aurora will automatically advise you on whether your string lengths are acceptable and can even string the system for you. However, as a solar professional, it’s still important to have an understanding of the rules that guide string sizing.
