Info What does this mean?

A status message, not a fault. It usually clears on its own and needs no action from you.

Fronius Inverter STATE 105 — Is Your Grid Frequency Too High?

STATE 105 means your Fronius inverter measured AC grid frequency above its permitted limit and disconnected from the grid, as required by grid standards. It reconnects automatically once the grid returns to normal — nothing in your inverter is broken.

What should I do first?

Two quick questions — we'll point you to the right starting point.

Is this code still showing on your inverter's display?

What this code means

In the Fronius status-code tables, STATE 105 is a Class 1 code with the description "AC frequency too high." Your inverter constantly watches the frequency of the utility grid it feeds into — 60 Hz in the US — and when the measured frequency climbs above the limit set by your country setup, it must stop feeding power. This is the inverter obeying the rules, not a failure.

Fronius is explicit about what Class 1 codes are: they "generally only arise momentarily and are caused by the public grid," and the manual gives this exact case as its example — "The grid frequency is too high and the inverter may not feed any energy into the grid owing to a standard. There is nothing wrong with the device." When 105 appears, the inverter disconnects, monitors the grid during the stipulated monitoring period, and resumes feeding once conditions are within the permitted range again. When it does restart, the GPIS SoftStart function ramps output power up gradually in line with national guidelines instead of slamming back on.

Common causes

['A momentary rise in frequency on the public utility grid. Fronius states Class 1 codes are caused by the public grid, and this is the overwhelmingly most likely trigger — your system is reacting to the grid, not failing.', 'A wider grid event or disturbance. Frequency is set by the utility network as a whole, so a regional grid incident can push frequency up briefly and trip multiple inverters at once.', 'A persistent grid-frequency condition on your local line. If the utility supply in your area runs near or above the trip limit, the code can appear more often than a one-off event.', "Frequency trip thresholds in your inverter's country setup. The permitted limits (shown as FIL/FOL values in the inverter's settings) are set to national standards — if they were ever adjusted away from the correct country setup, the inverter may trip more readily. Only your installer or a Fronius service tech should touch these."]

Safe steps to try

Work top to bottom, ticking off each step as you complete it. 0 of 1 done.

['Do nothing and watch. The inverter is running its mandatory grid-monitoring period and will reconnect on its own once frequency is back in range — this is the designed behavior.', 'Note what you see: write down STATE 105 and the time it appeared, in case it comes back.', "Check whether your home still has utility power. If the whole house is out, the cause is a grid outage and this message is just your inverter's way of saying so.", 'Look at your AC breakers (the solar breaker in your panel) to confirm nothing has tripped — flip nothing; just look.', "Open Fronius Solar.web or the app later and check the day's production. If output recovered on its own, the event is closed and no action is needed."]

Is your inverter still under warranty?

Before paying for a repair, check — your installer may fix this free.

Brand Year installed

Based on typical standard warranty terms — always confirm with your warranty card or installer paperwork, as terms vary by model, region, and purchase date.

When to call an electrician

Call your solar installer or a Fronius service technician if STATE 105 keeps recurring or is displayed constantly — the Fronius manual's stated remedy for Class 1 codes is to contact your system fitter when the status code keeps appearing. Also call a pro if the inverter feeds no energy for an entire sunny day, if the code appears alongside any burning smell, unusual heat, smoke, or sparking, or if anyone has recently changed the country-setup frequency limits.

Frequently asked questions

Can I reset STATE 105 myself?

There is nothing to reset. The inverter clears this status on its own through its grid-monitoring routine and reconnects automatically. No button press is required.

Does STATE 105 damage my panels or my inverter?

No. The code means the inverter protected itself and the grid by disconnecting. Your panels and inverter are unharmed — this is a protective response, not a malfunction.

How long before my inverter starts feeding power again?

Usually within minutes. The inverter must watch the grid for a stipulated monitoring period (GMTi/GMT reconnect time in your settings), then it resumes and the GPIS SoftStart ramps power back up gradually.

Is STATE 105 a fault I should worry about?

Not as a one-off. It is a Class 1 status message caused by the public grid — Fronius's own manual says there is nothing wrong with the device. It only becomes a service matter if it keeps coming back.

Can a grid frequency problem affect other electronics in my home?

Brief frequency excursions on the utility grid are a grid-operator concern and rarely affect household appliances, which are built to tolerate them. If the message recurs often, your installer can assess whether the grid conditions at your site are the issue.

Sources: meaning and troubleshooting verified against the manufacturer's documentation — Fronius Symo / Fronius Eco Operating Instructions, manuals.fronius.com (doc 4204101909) — Status Codes section, Class 1 status codes table (Code 105: "AC frequency too high"), Class 1 behavior description (disconnect, stipulated monitoring period, auto-resume, GPIS SoftStart), remedy: check grid connections; if the status code keeps recurring, contact your system fitter.