About this app
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
Latest release
What’s New
- Added larger conductor sizes: 250, 300, 350, 400, and 500 kcmil (copper and aluminum) for bigger AC and DC runs. - Resistance values follow NEC Chapter 9, Table 8. - Minor stability improvements.
Audience growth
Ratings growth
Baseline captured. Growth appears after the crawler observes a changed rating count.
Momentum comes from crawler snapshots for the tracked storefront. “Viral growth signal” means unusually fast recent rating gains; it is an indicator, not download data.
Price tracking
Price intelligence
First snapshot captured. The trend line starts after the next crawler price observation.
- First observed Oct 16, 2026 · 4:59 PM $0.99