You can refer to the Fronius inverter manual here.
Go to page 42 to find your particular Fronius inverter fault codes
Troubleshooting Fronius Fault Codes
Is there a fault code displaying on your Fronius Inverter?
Fronius Self Diagnosis Tests
As it says in this manual, the inverter is set up to run self diagnostic tests that automatically detect faults that may occur. The faults are listed as status codes, which you can look up in the Fault Code section of this manual.
Remember, status codes may sometimes appear briefly as a result of the inverter's control response. If the inverter then continues working with no sign of any problem, this means that there was no fault.
Fronius Status Codes Summaries
Class 1 status codes
Class 1 status codes generally only arise momentarily and are caused by the public grid.
Class 3 Status Codes
Class 3 includes status codes that may occur while feeding energy into the grid, but generally do not cause the process to be interrupted for any length of time.
| Code | Description | Beahaviour | Remedy |
|---|---|---|---|
| 301 | Overcurrent (AC) | Short-term interruption while feeding energy into the grid due to overcurrent in the inverter. The inverter resumes with its start-up routine. | Fault is rectified automatically; if this status code is displayed all the time: notify a Fronius trained service engineer |
| 302 | Overcurrent (DC) | Short-term interruption while feeding energy into the grid due to overcurrent in the inverter. The inverter resumes with its start-up routine. | Fault is rectified automatically; if this status code is displayed all the time: notify a Fronius trained service engineer | 303 | Power stage set overtemperature | Short-term interruption while feeding energy into the grid due to overtemperature The inverter resumes with its start-up routine. | Purge openings for cooling air and heat sink if necessary; fault is rectified automatically; if this status code keeps recurring, contact your system engineer | 304 | Internal temperature too high | Short-term interruption while feeding energy into the grid due to overtemperature. The inverter resumes with its start-up routine. | Purge openings for cooling air and heat sink if necessary; fault is rectified automatically; if this status code keeps recurring, contact your system engineer | 306* | LOW PV OUTPUT Intermediate circuit voltage too low for feeding energy into the grid | Short-term interruption while feeding energy into the grid. The inverter resumes with its start-up routine. | Purge openings for cooling air and heat sink if necessary; fault is rectified automatically; if this status code keeps recurring, contact your system engineer | 307* | LOW PV VOLTAGE DC input voltage too low for feeding energy into the grid | Short-term interruption while feeding energy into the grid. The inverter resumes with its start-up routine. | Purge openings for cooling air and heat sink if necessary; fault is rectified automatically; if this status code keeps recurring, contact your system engineer | 308 | Intermediate circuit overvoltage | Short-term interruption while feeding energy into the grid. The inverter resumes with its start-up routine. | Fault is rectified automatically; if this status code is displayed all the time: notify a Fronius trained service engineer | 309 | DC input voltage MPPT 1 too high | 3hort-term interruption while feeding energy into the grid. The inverter resumes with its start-up routine. | Fault is rectified automatically; if this status code is displayed all the time: notify a Fronius trained service engineer | 313 | DC input voltage MPPT 2 too high | hort-term interruption while feeding energy into the grid. The inverter resumes with its start-up routine. | Fault is rectified automatically; if this status code is displayed all the time: notify a Fronius trained service engineer |
IMPORTANT! Due to the low level of insolation, the status codes 306 (LOW PV OUTPUT) and 307 (LOW PV VOLTAGE) are displayed routinely every morning and evening. These status codes do not indicate any kind of fault.
Class 4 Status Codes
Class 4 Status Code may require a service technician
Class 5 Status codes
Class 5 status codes do not generally interfere with feeding energy into the grid, but can cause restrictions. These status codes are displayed until they are acknowledged by pressing a key (however, the inverter continues to operate normally in the background).
Class 7 status codes
Class 7 status codes relate to the control system, the configuration and inverter data recording, and may directly or indirectly affect the process of feeding energy into the grid.
Operation in dusty environments
When operating the inverter in extremely dusty environments you may need to clean the cooling elements and fan on the back of the inverter as well as the air intakes at the mounting bracket using clean compressed air.
If in doubt, call Heinz Solar, remember that Inverters are electrical equipment and may require expert technicians.