
STATE 735
The update file does not match the device, the update file is too old
The firmware update file found on the USB device is incompatible with the inverter, either because it was intended for a different model or the version is older than the currently installed firmware.

galvo

primo

symo
Expected Behaviors
- The inverter is displaying a STATE 735 message indicating a warning. It typically continues operating, but other errors may also be present. Press ENTER on the inverter to acknowledge the message and check the menu for additional status codes.
State Class
A state class is a generalized description of errors, catagorized by the number the STATE code starts with.
These errors involve internal memory systems, firmware data checks, or USB and update-related events. Most do not affect power production directly but can interfere with monitoring, data logging, or firmware updates. Persistent Class 7 codes should be checked by a Fronius Trained Service Partner to ensure system stability and correct operation.
- Check the update file. If necessary, download the correct update file for your device from the following link: FRONIUS FIRMWARE.

Fronius inverters in the U.S. typically come with a standard 10-year warranty. Starting in 2024, registering the inverter on the Fronius Solar.web website (the Fronius solar monitoring platform), extended the warranty by an additional 2 years, totaling 12 years of coverage, and updates the warranty start date to the actual installation date. Fronius has also offered warranty extensions of up to 20 years.
The inverter label, typically located on the bottom of the unit, lists the device serial number. To check if your inverter is still covered, call Fronius Technical Support at 1-877-Fro-nius (1-877-376-6487)
Founded in 1945 by Günter Fronius in Pettenbach, Austria, Fronius began as a repair shop for radios and electrical equipment. Recognizing the need for efficient battery charging, Günter developed a device to recharge car batteries, marking the company's first foray into energy solutions.


The best point of contact is your original installer
If the orginal installer is no longer available, contact a local Fronius Service Provider in your area.
Fronius Technical Support can also be reached at 1-877-Fro-nius (1-877-376-6487)
DENVER RESIDENTS: Is your system located in the Denver, CO metro area? CONTACT US