How to troubleshoot an Underperforming Array

Diagnose why your solar production is below estimate, working from the safest checks to the most involved. Covers establishing a baseline, reading monitoring data and inverter error codes, finding new shading and soiling, verifying the AC side, and — only where safe — checking string voltage. Emphasizes the hard rule that PV DC wiring is energized whenever the sun is on the panels and cannot simply be switched off.