EG4 › PV strings and input terminals
PV string reads a fraction of expected voltage
reported more than once
Symptoms
- One PV string on an 18kPV peaks at only about 16V versus roughly 185V expected for its panel count, while a second string on the same inverter peaks normally around 260V
- A large voltage drop between panels and inverter (confirmed as roughly 25%) undershoots the inverter's roughly 120V MPPT startup threshold
- And a newly installed FlexBOSS21 with 23 panels shows no PV voltage or current on any of its three MPPT inputs despite 170-400VDC measured correctly present at the terminals
The cause and the fix
Subscribers see the cause, the fixes that worked and who did them, part numbers and recent prices when a part is involved, and the field reports behind this entry.