Vmpp is the voltage at which the inverter recorded peak power today. MPPT tracking is the fraction of producing frames where operating voltage stayed within ±5 % of Vmpp — higher is better. Capacity factor is total kWh ÷ (peak W × hours of sun) — a daily measure of how close the string ran to its peak. Compare strings of equal panel count: they should be within ~10 % of each other on each metric.
| String | Vmpp | Impp | Pmpp | Daily kWh | MPPT | Avg V | Cap. factor |
|---|---|---|---|---|---|---|---|
| PV1 | 226.4 V | 17.2 A | 3823 W | 10.82 kWh | 29% | 252 V | 27.5% |
| PV2 | 193.2 V | 18.2 A | 3445 W | 7.31 kWh | 21% | 217.8 V | 21.1% |
| PV3 | 0 V | 0 A | 0 W | 0 kWh | 0% | 0 V | 0% |
Industry benchmark: 4 kWh/kWp/day is solid for SA fixed-tilt, 5+ is excellent. Drops below 2.5 on a sunny day suggest shading or array faults.
Healthy inverter holds ~95 % near rated load; efficiency dips at low power. Sustained drop = inverter aging or thermal issues.
Quick anomaly check — today's solar should look like recent sunny days.