Solar Inverter Sizer NEC 690

Solar Inverter Sizing per NEC 690.7(A)

# What it does
Calculates maximum input voltage and current for grid-tied and hybrid solar inverters per NEC 690.7(A) using cold-temperature Voc correction.

# Features
- Module Voc and Vmp inputs
- Series module count per string
- Cold-temperature voltage correction (NEC 690.7)
- Vmp at high temperature for MPPT range
- Inverter max input voltage check
- Imax = array Isc x 1.25 (NEC 690.8(A)(1)) vs inverter max DC input
- Multiple string configurations
- PASS / FAIL inverter compatibility

# Made for
Solar installers, PV system designers, NABCEP candidates, EPC engineers, code inspectors.

# Optional Pro Upgrade — $2.99 one-time
The following features require a separate one-time in-app purchase. They are not required to use the calculator:
- Calculation history (saved & searchable)
- PDF report export with NEC references
- Dark theme
- Ad-free experience