307 on a Fronius International GmbH Fronius SnapINverter: LOW PV VOLTAGE - DC input voltage too low for feeding energy into the grid
Short answer
On a Fronius International GmbH inverter, 307 means: LOW PV VOLTAGE - DC input voltage too low for feeding energy into the grid. The inverter keeps running with some functions stopped. An engineer is needed to fix the cause.
Reviewed 24 September 2026 · 1 source
What it means
The manual says: LOW PV VOLTAGE - DC input voltage too low for feeding energy into the grid.
Part involved: DC input.
When it shows: Class 3 status code.
Likely causes:
- Rectified automatically; routinely shown early morning and evening (not a fault); if it occurs with sufficient insolation contact your system engineer.
Is it safe?
| Does the inverter stop? | Partly |
|---|---|
| Severity | Information only |
| Engineer needed? | Yes |
The inverter keeps running with some functions stopped.
Resetting itself: yes.
Manual reset: Automatic when condition clears.
What you can check
- Read the state code on the inverter display or in Fronius Solar.web and note date/time for your installer.
- From the ground, check the panels are not covered by snow, leaves or dirt (Fronius UK support advice); never go on the roof.
- Fronius' UK homeowner support page asks you to check the inverter's DC switch is in the 'I' (on) position - only operate the switch on the inverter itself, never touch DC cables or connectors.
- Normal at dawn/dusk and in very dull weather.
What the engineer will check
- If shown in good sunlight: measure string open-circuit voltage, check DC connectors/isolators, module defects.
Who to ask for: Fronius-trained PV installer / Fronius Service Partner.
Certification: Qualified electrician (BS 7671; MCS-certified PV installer for work on the PV array/DC side).
What you might notice
Sources
- Fronius Primo 3.0-1 - 8.2-1 Operating Instructions (HTML) ↗ · 42,0410,2165 online edition · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026