Solar Voltage Drop

Solar Voltage Drop Calculator helps solar installers and electricians verify wire sizing for voltage drop compliance per NEC standards. Supports DC solar circuits (NEC 690.31, 2% threshold) and AC branch circuits (NEC 210.19, 3% threshold). Choose from AWG 14 through 4/0, copper or aluminum conductors, and DC, AC single-phase, or AC three-phase circuits. Features: - Voltage drop in volts and percentage - End voltage calculation - Pass/Fail indicator based on NEC thresholds - Automatic wire size recommendation when current selection fails - Save calculations to history - Export professional PDF reports - NEC Chapter 9 Table 8 resistance data Formula: VD = (multiplier x L x I x R) / 1000 - multiplier: 2 for DC/single-phase, 1.732 for three-phase - L = one-way distance (ft) - I = current (A) - R = resistance (ohms/1000ft) from NEC Chapter 9 Table 8 OPTIONAL PRO UPGRADE - $2.99 ONE-TIME IN-APP PURCHASE The following features require a separate one-time in-app purchase. They are not required to use the calculator: - Unlimited saved calculation history - PDF export of results - Dark theme - Ad-free experience