Overcurrent on DC side (PV2)
Fronius · Primo GEN24
What does 503 mean?
The Fronius Primo GEN24 208-240 inverter has detected an excessive current flowing from the PV2 string on the DC side. This suggests a potential short circuit within the PV2 array or an improper string configuration.
Common Causes
- Overcurrent on the DC side (PV2).
- Short circuit on the PV array.
- Incorrect PV array sizing or configuration.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Disconnect the PV2 string using the DC disconnector and visually inspect all PV modules, wiring, and connectors for any damage or indications of a short circuit.
- 2
Measure the open-circuit voltage (Voc) and short-circuit current (Isc) of the PV2 string and compare them against expected values from the module datasheet.
- 3
Confirm that the PV2 string configuration (number of modules in series and parallel) adheres to the Fronius Primo GEN24 208-240 inverter's maximum DC current specifications.
- 4
Inspect any external DC combiner box or array wiring associated with PV2 for potential short circuit conditions.
- 5
If external components are confirmed good, the fault might be internal to the inverter; contact Fronius service.