Fronius state 307 or 306 PV voltage low: what it means and what to do

Common causes

• Low sunlight in the early morning, the evening or at night. This is normal.
• Panels covered with snow, dirt or leaves.
• The DC switch at the bottom of the inverter in the off position.

Safe steps to try

1. Check the time of day If the code shows around sunrise or sunset and clears once the sun is up, nothing is wrong.
2. Look at the panels from the ground Check for snow, leaves or heavy dirt. Do not climb onto the roof.
3. Look at the DC switch position Fronius asks owners to make sure the DC switch at the bottom of the inverter is in the "I" (on) position. Look without touching; if it shows 0, tell your technician.
4. Call if it persists in good sun Fronius's remedy is to contact your installer if the code persists with sufficient sunlight.

Frequently asked questions

My Fronius shows 307 every morning. Is something broken?

No. Fronius states that 306 and 307 appear naturally every morning and evening due to low solar irradiance and are not the result of a fault.

What is the difference between 306 and 307?

Fronius uses 306 when the inverter's intermediate circuit voltage is too low to feed the grid, and 307 when the DC input voltage from the panels is too low. Both have the same causes and the same advice.

Other Fronius faults

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