What is the “Voltage Drop” and why is it critical for DC string cabling?

Because PV systems operate on DC, long cable runs can lead to significant voltage drops. To maximize the energy sent to the inverter, international best practices suggest keeping the voltage drop below 1% or 2%. This often requires choosing a larger cross-section (e.g., 6mm² or 10mm² instead of 4mm²) for longer cable runs.