DC voltage too low (PV1)
Fronius · Primo GEN24
What does 509 mean?
The Fronius Primo GEN24 208-240 inverter has detected that the DC voltage from the PV1 string is too low for operation. This means there is insufficient voltage to start or maintain power conversion, often due to low irradiance or issues with the PV array.
Common Causes
- DC voltage too low (PV1).
- Insufficient irradiation.
- Too few modules in series.
- Faulty PV modules.
- Dirty PV modules.
- Partial shading of the PV array.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Verify that there is sufficient solar irradiation on the PV1 string; check if it's operating during daylight hours and not heavily overcast.
- 2
Measure the open-circuit voltage (Voc) of the PV1 string at its input terminals on the Fronius Primo GEN24 208-240 inverter and compare it to the inverter's minimum operating voltage.
- 3
Count the number of PV modules in series for PV1 and confirm it meets the minimum string voltage requirement for the Fronius Primo GEN24 208-240 inverter.
- 4
Inspect PV1 modules for dirt, dust, snow, or any partial shading that could significantly reduce voltage.
- 5
Check all connections within the PV1 string for loose wiring or damaged bypass diodes within modules that could reduce string voltage.