How do you determine the number of panels in a solar string?

String sizing ensures operating voltage stays within inverter input window across all conditions. Maximum string voltage (cold temperature, high irradiance): Voc(T) = Voc_STC * (1 + TempCoeff * (T_min - 25)) must not exceed inverter max input. Minimum string voltage (hot temperature, low irradiance): Vmp(T) at T_max must exceed inverter MPPT minimum. Calculate panel count: Max panels = Inverter_Vmax / Voc_cold. Min panels = Inverter_Vmppt_min / Vmp_hot. Choose integer within this range. Temperature coefficients (typically -0.3%/C for Voc) are critical.