Fronius Solar Error Codes Troubleshoot Guide

Are you seeing an error code on your inverter or solar system, but unsure what it means? This troubleshooting guide to Fronius solar error codes can help.

Both Fronius inverters and transformers will show error codes – known as STATE codes – when something is wrong. These STATE codes are key to resolving whatever issues you’re having with your Fronius product.

Using this troubleshooting guide, you can find the relevant error codes for your product to find the quickest and most efficient solution.

Fronius Inverter Error Codes & What To Do About Them

The Fronius solar inverter error codes are categorised by the first number in the sequence. The categories of error codes include:

-1xx: A 1xx code is usually temporary, caused by the power from the electrical mains (grid) being outside the inverters operating parameters.

-2xx: A 2xx code is a message from the grid monitoring device (ENS) integrated within the inverter that refers to the parameters of the public mains.

-3xx: A 3xx code can occur during grid feed-in operation.

-4xx: A 4xx error is triggered by faulty hardware or a software problem that requires the intervention of a Fronius Service Partner.

-5xx: A 5xx code generally does not stop the feed-in operation, but will continue to show until the message is acknowledged by pushing a button on the display.

-6xx: A 6xx error code indicates the necessary intervention by a Fronius trained service engineer or Fronius Service Partner.

-7xx: A 7xx error code relates to the control system, the configuration and inverter data recording, and may directly or indirectly affect the process of feeding energy into the grid.

The following tables list the different error codes for different Fronius products, including the Fronius IG, Primo, Symo and GALVO inverters.

Fronius IG Inverter Error Codes

The Fronius IG Inverter is a single-phase inverter with power categories from 1.5 to 5 kW.

Fronius IG STATE codes beginning with 1xx

Error Code Description of Error What to Do
STATE 101
Grid voltage beyond permitted limits. Caused by:
1. Mains voltage error
2. Incorrect values in the service menu
3. Internal fault
1. Check grid voltage, check circuit breakers are ON.
2. Change values in the service menu.
3. If problem persists contact your Fronius Service Partner.
STATE 104
Mains frequency beyond permitted limits. Caused by:
1. Mains frequency error
2. Incorrect values in the service menu
3. Internal fault
1. Check mains frequency, check circuit breakers are ON.
2. Change values in the service menu.
3. If a problem persists, contact your Fronius Service Partner.
STATE 107
Synchronisation with the public mains supply not possible. Caused by:
1. Mains not connected
2. Incorrect values in the service menu
3. Internal fault
1. Connect mains power, check circuit breakers are ON.
2. Check values in the service menu.
3. If a problem persists, contact your Fronius Service Partner.
STATE 108
Islanding detected. Caused by:
1. Islanding detected
2. Severe disturbances in public mains
3. Internal fault
1. Automatic correction
2. If a problem persists, contact your Fronius Service Partner.

Fronius IG STATE codes beginning with 2xx

Error Code Description of Error What to Do
STATE 201
Grid voltage beyond permitted limits. Caused by: 
1. Mains voltage error
2. Incorrect values in the service menu
3. Internal fault
1. Check grid voltage, check circuit breakers are ON.
2. Change values in the service menu.
3. If a problem persists, contact your Fronius Service Partner.
STATE 202
Grid voltage is lower than the specified limit. Caused by:
1. Grid voltage error on the public mains
2. Internal fault
1. Check grid voltage.
​​​​​​​2. If a problem persists, contact your Fronius Service Partner
STATE 203
Grid frequency is higher than the specified limit. Caused by:
1. Grid frequency error on the public mains
2. Internal fault
1. Check grid frequency.
2. If a problem persists, contact your Fronius Service Partner.
STATE 204
Grid frequency is lower than the specified limit. Caused by:
1. Grid frequency error on the public mains
2. Internal fault
1. Check grid frequency.
2. If a problem persists, contact your Fronius Service Partner.
STATE 205
Change of public mains impedance. Caused by:
1. Serious disturbances on the public mains
2. Internal fault
1. Reinforce mains cables.
2. Connect Fronius IG inverter to another phase.
3. If a problem persists, contact your Fronius Service Partner.
STATE 206
Absolute value of the impedance is too high. Caused by:
1. Mains impedance too high
2. Internal fault
1. Reinforce mains cables.
2. Connect Fronius IG inverter to another phase.
3. If a problem persists, contact your Fronius Service Partner.
STATE 207
The Mains relay does not open in spite of the switch off signal.
If a problem persists, contact your Fronius Service Partner.
STATE 208
The Mains relay does not close in spite of the switch on signal. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.

Fronius IG STATE codes beginning with 3xx

Error Code Description of Error What to Do
STATE 301
Safety circuit detects a current peak on the mains supply. Caused by:
1. Voltage drop on the public mains
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner
STATE 302
Safety circuit detects a current peak on the PV generator side. Caused by:
1. Voltage drop on the public mains supply
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 303
Heat sink temperature on the DC-AC board is too high. Caused by:
1. Ventilation slot congested
2. Very high ambient temperature
3. Distance between inverters too small
4. Internal fault
1. Free ventilation slot.
2. Change location of inverter.
3. Increase distance between inverters.
4. If a problem persists, contact your Fronius Service Partner.
STATE 304
Heat sink temperature on the DC-DC board is too high. Caused by:
1. Ventilation slot congested
2. Very high ambient temperature
3. Distance between inverters too small
4. Internal fault
1. Free ventilation slot.
2. Change location of inverter.
3. Increase distance between inverters.
4. If a problem persists, contact your Fronius Service Partner.
STATE 305
Feed-in process not possible, even though public mains parameter within the limits. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 306
POWER LOW. Caused by an intermediate circuit voltage has dropped below the permissible threshold value for feed in.
1. Check panels.
2. Internal fault.
STATE 307
DC LOW. Caused by:
1. DC-input voltage is too low for feed in
2. Internal fault
1. Check panels.
2. Internal fault.
STATE 308
Intermediate circuit voltage out of the maximum limit. Caused by:
1. Public mains disturbances
2. Internal fault
1. Reinforce mains cable.
2. If a problem persists, contact your Fronius Service Partner.

Fronius IG STATE codes beginning with 4xx

Error Code Description of Error What to Do
STATE 401
Communication error between IG control and the DC-DC board. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 402
Write access to the internal Fronius IG memory failed. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 403
The area in the internal memory for the country setting is incomplete. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 404
Connection between the control unit and the ENS is faulty. Caused by:
1. Public mains not connected
2. Internal fault
1. Check the public mains.
2. If a problem persists, contact your Fronius Service Partner.
STATE 405
An old or incorrect version of the ENS microprocessors has been recognised. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 406
Temperature sensor on the DC-AC board faulty or not connected. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 407
Temperature sensor on the DC-DC board faulty or not connected. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 408
Unsymmetry on the public mains detected. Caused by:
1. Public mains disturbances
2. Internal fault
1. Error is remedied automatically.
2. If a problem persists, contact your Fronius Service Partner.
STATE 409
Supply of the DC-AC board is not available. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 410
Service plug on the DC-AC board is not set correctly. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 412
Value for the fixed voltage is set higher than the open circuit voltage of the PV generator. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 413
Open circuit voltage is too high at the moment of transformer switching. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 414
Memory array for Fronius IG type in EE-PROM faulty. Caused by:
1. One-off – memory error
2. Internal fault
1. Error is remedied automatically.
2. If a problem persists, contact your Fronius Service Partner.
STATE 415
No END-enabling signal despite release by IG-control. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 416
Communication error between IG-Control and power stack. Caused by:
1. One-off – communication error
2. Internal fault
1. Error is remedied automatically.
2. If a problem persists, contact your Fronius Service Partner.
STATE 419
Two or more power stacks with identical Unique ID. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 420
Incomplete number of power stacks detected after reaching online threshold according to device type. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 421
Hardware ID sequence error. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 425
Receive time-out for data exchange with one or more power stacks exceeded. Caused by:
1. One off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 431
All power stacks are in boot mode. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.
STATE 432
Consistent error in power stack management. Caused by:
1. One off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 433
Allocation error of dynamic addresses. Caused by:
1. One off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 434
Ground fault detected. Caused by:
1. One off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner
STATE 435
Wrong configuration for EE-Prom. Caused by:
1. One off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 436
Error transmission faulty. Caused by:
1. One off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner
STATE 437
Power stack work around is active. Caused by:
1. One off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 438
Error during state code transmission. Caused by:
1. One off error
2. Permanent error
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 441
Power rack fan faulty. Caused by an internal fault
If a problem persists, contact your Fronius Service Partner.
STATE 442
Master for one phase could not be assigned. Caused by:
1. Temporary communication error
2. Internal fault
1. Error is remedied automatically.
2. If a problem persists, contact your Fronius Service Partner.
STATE 443
DC-DC energy transfer failure. Caused by:
1. Error during switching on a power stack
2. Internal fault
1. Error is remedied automatically.
2. If a problem persists, contact your Fronius Service Partner.
STATE 444
AC monitoring self test interrupted. During the self test another error occurred.
Quit the self test by pressing ESC and remedy the failure according to the error code list.

Fronius IG STATE codes beginning with 5xx

Error Code Description of Error What to Do
STATE 501
Heat sink temperature too high, although Fronius IG is on low output. Caused by:
1. Ventilation slot congested
2. Internal fault
1. Free ventilation slot.
2. If a problem persists, contact your Fronius Service Partner.
STATE 502
An isolation fault between DC+ or DC- to earth has been detected. Caused by isolation fault at the solar generator.
Check cables and the solar generator.
STATE 504
An error occurred while scanning LocalNet addresses. Caused by Identical Fronius IG address used twice.
Check the address of the inverters and other components.
STATE 505
The area in the internal memory for the “Setup” values is incomplete. Caused by:
1. One off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 506
The area in the internal memory for the “Total” values is incomplete. Caused by:
1. One off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner
STATE 507
The area in the internal memory for the “Day/Year” values is incomplete. Caused by:
1. One off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 508
The area in the internal memory for the “WR number” is damaged. Caused by:
1. One off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 509
No feed in operation for 24 hours. Caused by:
1. Snow covered or very dirty solar panels.
2. Insufficient power from the solar panels for feed in operation.
3.Internal error.
1. Clean solar panels or remove snow.
2. If a problem persists, contact your Fronius Service Partner.
STATE 510
Errors detected by LocalNet self diagnostic system. Caused by:
1. One-off memory error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 511
Errors detected by LocalNet Sensor Card self diagnostic system. Caused by:
1. One-off memory error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 512
According to the device type too many power stacks have been detected. Caused by:
1. One-off memory error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 513
Power stacks in boot mode. Caused by:
1. One-off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner
STATE 514
Incomplete number of power stacks detected after reaching online threshold – Device type. Caused by:
1. One-off error
2. Internal fault
1. Automatic correction.
2. If a problem persists, contact your Fronius Service Partner.
STATE 515
One or more power stacks notified STATE 406/ 407/ 409/ 410. Caused by an internal fault.
If a problem persists, contact your Fronius Service Partner.

Fronius Primo Inverter Error Codes

The Fronius Primo is a transformerless and compact single-phase inverter that is ideal for residential and small-scale commercial applications with power categories from 3.8 to 8.2 kW.

Fronius Primo STATE codes beginning with 1xx

Error Code Description of Error What to Do
STATE 102
AC voltage too high. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 103
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 105
AC frequency too high. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 106
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 107
AC grid outside the permissible limits. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 108
Stand alone operation detected. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 112
RCMU error. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.

Fronius Primo STATE codes beginning with 3xx

Error Code Description of Error What to Do
STATE 301
Overcurrent (AC). Short-term interruption while feeding energy into the grid due to over current in the inverter.The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 302
Overcurrent (DC). Short-term interruption while feeding energy into the grid due to over current in the inverter.The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 303
Power stage set over temperature. Short term interruption while feeding energy into the grid due to over temperature.The inverter resumes with its startup routine.
Purge openings for cooling air and heat sink if necessary; fault is rectified automatically; if this STATE code keeps recurring contact your solar power system installer.
STATE 304
Internal temperature is too high. Short term interruption while feeding energy into the grid due to over temperature.The inverter resumes with its startup routine.
Purge openings for cooling air and heat sink if necessary; fault is rectified automatically; if this STATE code keeps recurring contact your solar power system installer.
STATE 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 startup routine.
Fault is rectified automatically; if this STATE code occurs when there is sufficient insolation (sunlight) contact your solar power system installer.IMPORTANT! Due to the low level of insolation (sunlight) early in the morning and in the evening, the STATE codes 306 (LOW PV OUTPUT) and 307 LOW PV VOLTAGE) are displayed routinely at these times of day. These STATE codes do not indicate any kind of fault.
STATE 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 startup routine.
Fault is rectified automatically; if this STATE code occurs when there is sufficient insolation (sunlight) contact your solar power system installer.IMPORTANT! Due to the low level of insolation (sunlight) early in the morning and in the evening, the STATE codes 306 (LOW PV OUTPUT) and 307 LOW PV VOLTAGE) are displayed routinely at these times of day. These STATE codes do not indicate any kind of fault.
STATE 308
Intermediate circuit overvoltage. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 309
DC input voltage MPPT 1 too high. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 313
DC input voltage MPPT 2 too high. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.

Fronius Primo STATE codes beginning with 4xx

Error Code Description of Error What to Do
STATE 401
No communication with the power stage set is possible. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 406
Power stage set temperature sensor faulty. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 407
Internal temperature sensor faulty. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 408
DC feeding into the grid detected. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 412
Fixed voltage mode has been selected instead of MPP voltage mode and the fixed voltage has been set to too low or too high a value
If this STATE code persists contact your solar power system installer
STATE 415
Safety cut out via option card or RECERBO has triggered. The inverter is not feeding any energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 416
No communication possible between power stage set and control system. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 417
Hardware ID problem. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 419
Unique ID conflict. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 421
HID range error. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 425
No communication possible with the power stage set. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 426-428
Possible hardware fault. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 431
Software problem. The inverter is not feeding any energy into the grid.
Carry out an AC reset (switch the AC circuit breaker off and on); update the firmware; if this status code is displayed all the time please contact your local Fronius Service Partner.
STATE 436
Functional incompatibility (one or more PC boards in the inverter are not compatible with each other, e.g. after a PC board has been replaced. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
Update the inverter firm ware; if this status code is displayed all the time please contact your local Fronius Service Partner.
STATE 437
Power stage set problem. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
Update the inverter firm ware; if this status code is displayed all the time please contact your local Fronius Service Partner.
STATE 438
Functional incompatibility (one or more PC boards in the inverter in the inverter are not compatible with each other, e.g. after a PC board has been replaced). The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
Update the inverter firm ware; if this status code is displayed all the time please contact your local Fronius Service Partner.
STATE 443
Intermediate circuit voltage too low or asymmetric. The inverter is not feeding any energy into the grid.
If the status code is displayed all the time contact your local Fronius Service Partners.
STATE 445
Invalid limit value settings. The inverter is not feeding any energy into the grid for safety reasons.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 447
Insulation fault. The inverter is not feeding any energy into the grid for safety reasons.
If this status code is displayed all the time: notify a local Fronius Service Partner
STATE 448
Neutral conductor not connected. The inverter is not feeding any energy into the grid for safety reasons.
If this status code is displayed all the time: notify a local Fronius Service Partner
STATE 450
Guard cannot be found. The inverter is not feeding any energy into the grid for safety reasons.
If this status code is displayed all the time: notify a local Fronius Service Partner
STATE 452
Memory error detected. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time: notify your local Fronius Service Partner.
STATE 452
Communication error between the processors. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time: notify your local Fronius Service Partner.
STATE 453
Short term grid voltage error. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time: notify your local Fronius Service Partner.
STATE 454
Short term grid frequency error. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time: notify your local Fronius Service Partner.
STATE 456
Anti-islanding function is no longer implemented correctly. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time: notify your local Fronius Service Partner.
STATE 457
Grid relay sticking. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 459
Error when recording the measuring signal for the insulation test. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 460
Reference voltage source for the digital signal processor (DSP) is working out of tolerance. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 461
Fault in the DSP data memory. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 462
Error with DC feed monitoring routine. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 463
Reversed AC polarity, AC connector inserted incorrectly. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 474
If this STATE code keeps recurring, contact your solar power system installer
If this STATE code keeps recurring, contact your solar power system installer
STATE 475
Solar panel ground fault, insulation fault (connection between solar panel and ground). The inverter is not feeding any energy into the grid.
If this STATE code keeps recurring, contact your solar power system installe
STATE 476
Driver supply voltage is too low. The inverter is not feeding any energy into the grid.
If this STATE code keeps recurring, contact your solar power system installer
STATE 480, 481
Functional incompatibility (one or more PC boards in the inverter are not compatible with each other, e.g. after a PC board has been replaced). The inverter is not feeding any energy into the grid.
Update the inverter firmware; if the STATE code persists contact your local Fronius Service Partner
STATE 482
Startup incomplete. The inverter is not feeding any energy into the grid.
Perform AC reset (turn AC circuit breaker off and on), complete startup.
STATE 483
Voltage UDC fixed on MPP2 string out of limits. The inverter is not feeding any energy into the grid.
Check the MPP settings; if the status code is displayed all the time contact your local Fronius Service Partner
STATE 485
CAN transmit buffer is full. The inverter is not feeding any energy into the grid.
Carry out an AC reset (turn AC circuit breaker off and on), if the STATE code continues to be displayed notify your local Fronius Service Partner.

Fronius Primo STATE codes beginning with 5xx

Error Code Description of Error What to Do
STATE 502
Insulation error on the solar panels. Warning message is shown on the display.
If this STATE code keeps recurring, contact your solar power system installer.
STATE 509
No energy fed into the grid in the past 24 hours. Warning message is shown on the display.
Acknowledge STATE code; check whether all the conditions for the problem free feeding of energy into the grid have been met. If the STATE code is displayed all the time: look out for further STATE codes.
STATE 515
No communication with filters possible. Warning message is shown on the display.
If the status code is displayed all the time, notify your local Fronius Service Partner.
STATE 516
No communication possible with the storage unit.Storage unit warning message.
If the status code is displayed all the time, notify your local Fronius Service Partner.
STATE 517
Derating caused by too high a temperature. When power derating occurs, a warning message is shown on the display
Purge cooling air openings and heat sink if necessary; fault is rectified automatically. If this STATE code keeps recurring contact your solar power system installer.
STATE 522
DC1 Input Voltage too low: the DC voltage on input 1 of the inverter is too low.
Check voltage and polarity on input 1 of the inverter. If this STATE code keeps recurring please contact your solar power system installer.
STATE 523
DC2 Input Voltage too low: the DC voltage on input 2 of the inverter is too low.
Check voltage and polarity on input 2 of the inverter. Check MPP settings / voltage at the “Installer Menu Basic”. If this STATE code keeps recurring please contact your solar power system installer.
STATE 558
Functional incompatibility (one or more PC boards in the inverter are not compatible with each other, e.g. after a PC board has been replaced). Possible error displays or malfunction on the inverter.
If this STATE code keeps recurring contact your solar power system installer
STATE 560
Derating caused by over-frequency. This STATE code is displayed when the grid frequency becomes excessively high. The inverter will then reduce its output. The status indicator will continue to be displayed until the inverter has returned to normal operation.
As soon as the grid frequency is back within the permissible range and the inverter has returned to normal operation, the fault is rectified automatically. If this STATE code keeps recurring, contact your solar power system installer.
STATE 566
Arc detector switched off (e.g. during external arc monitoring). The STATE code is displayed every day until the arc detector is reactivated.
No error, Confirm status code by pressing ‘Enter’.
STATE 567
Grid Voltage Dependent Power Reduction is active. This state code is a warning informing you that the Grid Voltage Dependent Power Reduction mode (GVDPR or Volt – Watt mode) has been activated and the inverter will continue to operate with reduced power output. This is because the grid voltage has exceeded 250Vac and the GVDPR has been enabled to try to reduce the voltage rise at the inverters terminals. This mode must be enabled by default in accordance with the latest Australian Standards.
Acknowledge status code. If this STATE 567 code keeps recurring contact your local solar power system installer.

Fronius Primo STATE codes beginning with 7xx

Error Code Description of Error What to Do
STATE 705
Conflict when setting the inverter number (e.g. number already assigned).
Correct the inverter number via the setup menu.
STATE 721
EEPROM has been reinitialised or EEPROM is faulty. Warning message is shown on the display.
Acknowledge STATE code; If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 731
Initialisation error – USB stick is not supported. Warning message is shown on the display.
Check or replace the USB stick. Check the file system on the USB stick. If the STATE code is displayed all the time, notify your local Fronius Service Partner.
STATE 732
Over current on USB stick. Warning message is shown on the display.
Check or replace the USB stick. Check the file system on the USB stick. If the STATE code is displayed all the time, notify your local Fronius Service Partner.
STATE 733
No USB stick connected. Warning message is shown on the display.
Connect or check the USB stick. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 734
Update file not recognised or not present. Warning message is shown on the display.
Check update file (e.g. for correct file name). If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 735
Update file does not match the device, update file too old. Warning message appears on the display, update process is interrupted.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 736
Write or read error occurred.Warning message is shown on the display.
Check USB stick and the data contained on it or replace USB stick.Never unplug a USB stick if the ‘Data Transmission’ LED is still flashing or lit. If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 738
Log file cannot be saved (e.g. USB stick is write protected or full). Warning message is shown on the display.
Create storage space, remove write protection, check or replace USB stick if necessary.If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 743
Error occurred during the update process. Warning message is shown on the display.
Repeat the update process, check the USB stick. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 745
Update file is corrupt. Warning message appears on the display, update process is interrupted.
Redownload the firmware. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 751
Time lost. Warning message is shown on the display.
Reset the time and date on the inverter. Check update file (e.g. for correct file name). If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 752
Real Time Clock module communication error. Warning message is shown on the display.
Reset the time and date on the inverter. Check update file (e.g. for correct file name). If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 757
Hardware error in the Real Time Clock module. Error message is shown on the display; the inverter is not feeding any energy into the grid.
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 758
Internal error: Real Time Clock module is in emergency mode. Time may be inaccurate or lost (feeding energy into the grid normally).
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 766
Emergency power de-rating has been activated. Error message is shown on the display.
If STATE code is displayed all the time contact your local Fronius Service Partner.

Fronius Symo Inverter Error Codes

The Fronius Symo is a three-phase solar inverter in the SnapINverter range with power categories ranging from 3.0 to 8.2 kW.

Fronius Symo STATE codes beginning with 1xx

fronius symo inverter, white and black, square shape
Error Code Description of Error What to Do
STATE 102
The AC voltage is too high. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 103
The AC voltage is too low. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 105
AC frequency is too high. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 106
The AC frequency is too low. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 107
AC grid outside the permissible limits. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 108
Stand alone operation detected. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 112
RCMU error. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.

Fronius Symo STATE codes beginning with 3xx

Error Code Description of Error What to Do
STATE 301
Overcurrent (AC). Short-term interruption while feeding energy into the grid due to over current in the inverter.The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 302
Overcurrent (DC). Short-term interruption while feeding energy into the grid due to over current in the inverter.The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 303
DC module over temperature. Short term interruption while feeding energy into the grid due to over temperature.The inverter resumes with its startup routine.
Purge openings for cooling air and heat sink if necessary; fault is rectified automatically; if this STATE code keeps recurring contact your solar power system installer.
STATE 304
AC module over temperature. Short term interruption while feeding energy into the grid due to over temperature.The inverter resumes with its startup routine.
Purge openings for cooling air and heat sink if necessary; fault is rectified automatically; if this STATE code keeps recurring contact your solar power system installer.
STATE 305
No power being fed in, despite the closed relay. Short term interruption while feeding energy into the grid due to over temperature.The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code keeps recurring, contact your solar power system installer.
STATE 306
PV output is too low for feeding energy into the grid. Short term interruption while feeding energy into the grid.The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code occurs when there is sufficient insolation (sunlight) contact your solar power system installer.IMPORTANT! Due to the low level of insolation (sunlight) early in the morning and in the evening, the STATE codes 306 (LOW PV OUTPUT) and 307 LOW PV VOLTAGE) are displayed routinely at these times of day. These STATE codes do not indicate any kind of fault.
STATE 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 startup routine.
Fault is rectified automatically; if this STATE code occurs when there is sufficient insolation (sunlight) contact your solar power system installer.IMPORTANT! Due to the low level of insolation (sunlight) early in the morning and in the evening, the STATE codes 306 (LOW PV OUTPUT) and 307 LOW PV VOLTAGE) are displayed routinely at these times of day. These STATE codes do not indicate any kind of fault.
STATE 308
Intermediate circuit voltage is too high. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner
STATE 309
DC input voltage MPPT 1 too high. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 311
Polarity of DC strings reversed. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 313
DC input voltage MPPT 2 too high. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 314
Current sensor calibration timeout. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 315
AC current sensor error. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 316
Interrupt Check fails. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 325
Overtemperature in the connection area. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 326
Fan 1 error. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 327
Fan 2 error. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically; if this STATE code is displayed all the time: notify your local Fronius service partner.

Fronius Symo STATE codes beginning with 4xx

Error Code Description of Error What to Do
STATE 401
No communication possible with the power stage set. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 406
AC module temperature sensor faulty (L1). The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 407
AC module temperature sensor faulty (L2). The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 408
The DC component measured in the grid is too high. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 412
Fixed voltage mode has been selected instead of MPP voltage mode and the fixed voltage has been set to too low or too high a value
If this STATE code persists contact your solar power system installer.
STATE 415
Safety cut out via option card or RECERBO has triggered. The inverter is not feeding any energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 416
No communication possible between power stage set and control system. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 417
Hardware ID problem.The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 419
Unique ID conflict. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 420
No communication possible with the Hybrid manager. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 421
HID range error. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 425
No communication with the power stage set possible. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 426-428
Possible hardware fault. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 431
Software problem. The inverter is not feeding any energy into the grid.
Carry out an AC reset (switch the AC circuit breaker off and on); update inverter firmware; if this status code is displayed all the time please contact your local Fronius Service Partner.
STATE 436
Functional incompatibility (one or more PC boards in the inverter are not compatible with each other, e.g. after a PC board has been replaced. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 437
Power stage set problem. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 438
Functional incompatibility (one or more PC boards in the inverter in the inverter are not compatible with each other, e.g. after a PC board has been replaced). The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 443
Intermediate circuit voltage too low or asymmetric. The inverter is not feeding any energy into the grid.
If the status code is displayed all the time contact your local Fronius Service Partners.
STATE 445
– Compatibility error (e.g. due to replacement of a PC board)– invalid power stage set configuration. The inverter is not feeding any energy into the grid for safety reasons.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 447
Insulation fault. The inverter is not feeding any energy into the grid for safety reasons.
If this status code is displayed all the time: notify a local Fronius Service Partner.
STATE 448
Neutral conductor not connected. The inverter is not feeding any energy into the grid for safety reasons.
If this status code is displayed all the time: notify a local Fronius Service Partner.
STATE 450
Guard cannot be found. The inverter is not feeding any energy into the grid for safety reasons.
If this status code is displayed all the time: notify a local Fronius Service Partner.
STATE 451
Memory error detected. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time: notify your local Fronius Service Partner.
STATE 452
Communication error between the processors. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time: notify your local Fronius Service Partner.
STATE 453
Grid voltage and power stage set are incompatible. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time: notify your local Fronius Service Partner.
STATE 454
Grid frequency and power stage set are incompatible. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time: notify your local Fronius Service Partner.
STATE 456
Anti-islanding function is no longer implemented correctly. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time: notify your local Fronius Service Partner.
STATE 457
Grid relay sticking or the neutral conductor ground voltage is too high. The inverter is not feeding any energy into the grid.
Check the grounding (the neutral conductor ground voltage must be less than 30V. If a problem persists contact your local Fronius Service Partner.
STATE 458
Error when recording the measuring signal. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 459
Error when recording the measuring signal for the insulation test. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 460
Reference voltage source for the digital signal processor (DSP) is working out of tolerance. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 461
Fault in the DSP data memory. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 462
Error with DC feed monitoring routine. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 463
Reversed AC polarity, AC connector inserted incorrectly. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 474
RCMU sensor faulty.The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 475
Solar panel ground fault, insulation fault (connection between solar panel and ground). The inverter is not feeding any energy into the grid.
Solar panel ground fault, insulation fault (connection between solar panel and ground). The inverter is not feeding any energy into the grid.
STATE 476
Driver supply voltage too low. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 480, 481
Functional incompatibility (one or more PC boards in the inverter are not compatible with each other, e.g. after a PC board has been replaced).The inverter is not feeding any energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 482
Setup after the initial start-up was interrupted. The inverter is not feeding any energy into the grid.
Perform AC reset (turn AC circuit breaker off and on), complete startup.
STATE 483
Voltage UDC fixed on MPP2 string out of limits. The inverter is not feeding any energy into the grid.
Check the MPP settings; if the status code is displayed all the time contact your local Fronius Service Partner
STATE 485
CAN transmit buffer is full.The inverter is not feeding any energy into the grid.
Carry out an AC reset (turn AC circuit breaker off and on), if the STATE code continues to be displayed notify your local Fronius Service Partner.

Fronius Symo STATE codes beginning with 5xx

Error Code Description of Error What to Do
STATE 502
Insulation error on the solar panels. Warning message is shown on the display.
If this STATE code keeps recurring, contact your solar power system installer.
STATE 509
No energy fed into the grid in the past 24 hours. Warning message is shown on the display.
Acknowledge STATE code; check whether all the conditions for the problem free feeding of energy into the grid have been met. If the STATE code is displayed all the time: look out for further STATE codes.
STATE 515
No communication with the filter possible. Warning message is shown on the display.
If the status code is displayed all the time, notify your local Fronius Service Partner.
STATE 516
No communication possible with the storage unit. Storage unit warning message.
If the status code is displayed all the time, notify your local Fronius Service Partner.
STATE 517
Power derating caused by too high a temperature. When power derating occurs, a warning message is shown on the display.
Purge cooling air openings and heat sink if necessary; fault is rectified automatically; if this STATE code keeps recurring contact your solar power system installer.
STATE 518
Internal DSP malfunction. Warning message on the display.
If this STATE code keeps recurring contact your solar power system installer.
STATE 519
No communication possible with the storage unit. Storage unit warning message.
If this STATE code keeps recurring contact your solar power system installer.
STATE 520
No energy fed into the grid by MPPT1 in the past 24 hours. Warning message is shown on the display.
Acknowledge status code; check whether all the conditions for the problem free feeding of energy into the grid has been met. If this STATE code keeps recurring contact your solar power system installer.
STATE 522
DC low string 1. Warning message is shown on the display.
Warning message on the display
STATE 523
DC low string 2. Warning message is shown on the display.
Warning message on the display
STATE 558, 559
Functional incompatibility (one or more PC boards in the inverter are not compatible with each other, e.g. after a PC board has been replaced). Warning message is shown on the display.
Update the inverter firmware;if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 560
Derating caused by over-frequency. This STATE code is displayed when the grid frequency becomes excessively high. The inverter will then reduce its output. The status indicator will continue to be displayed until the inverter has returned to normal operation.
As soon as the grid frequency is back within the permissible range and the inverter has returned to normal operation, the fault is rectified automatically. If this STATE code keeps recurring contact your solar power system installer.
STATE 564
Functional incompatibility (one or more PC boards in the inverter are not compatible with each other, e.g. after a PC board has been replaced). Warning message on the display.
Update the inverter firmware if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 566
Arc detector switched off (e.g. during external arc monitoring). The STATE code is displayed every day until the arc detector is reactivated.
No errorConfirm status code by pressing ‘Enter’.
STATE 567
Grid Voltage Dependent Power Reduction is active. This state code is a warning informing you that the Grid Voltage Dependent Power Reduction mode (GVDPR or Volt – Watt mode) has been activated and the inverter will continue to operate with reduced power output. This is because the grid voltage has exceeded 250Vac and the GVDPR has been enabled to try to reduce the voltage rise at the inverters terminals. This mode must be enabled by default in accordance with the latest Australian Standards.
If this STATE code keeps recurring contact your solar power system installer.

Fronius Symo STATE codes beginning with 6xx

Error Code Description of Error What to Do
STATE 601
CAN bus is full. The inverter is not feeding any energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 603
AC module temperature sensor faulty (L3). The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If this STATE code keeps recurring contact your solar power system installer.
STATE 604
DC module temperature sensor faulty. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If this STATE code keeps recurring contact your solar power system installer.
STATE 607
RCMU error. The inverter is not feeding any energy into the grid.
Reset status code by pressing ‘Enter’. The inverter resumes the feeding of energy into the grid; if the status code keeps appearing, check the complete solar system for damage.
STATE 608
Functional incompatibility (one or more PC boards in the inverter are not compatible with each other, e.g. after a PC board has been replaced). The inverter is not feeding any energy into the grid.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.

Fronius Symo STATE codes beginning with 7xx

Error Code Description of Error What to Do
STATE 701-716
Provides information about the internal processor status. Warning message is shown on the display.
If the STATE code is displayed all the time notify your local Fronius Service Partner.
STATE 721
EEPROM has been re-initialised. Warning message is shown on the display.
Acknowledge STATE code; If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 722-730
Provides information about the internal processor status. Warning message is shown on the display
If the STATE code is displayed all the time contact your local Fronius Service Partner
STATE 731
Initialisation error – USB flash drive is not supported. Warning message is shown on the display.
Check or replace USB flash drive. Check the file system on the USB flash drive. If the STATE code is displayed all the time notify your local Fronius Service Partner.
STATE 732
Initialisation error – Over current on USB stick. Warning message is shown on the display.
Check or replace USB flash drive. Check the file system on the USB flash drive. If the STATE code is displayed all the time notify your local Fronius Service Partner.
STATE 733
No USB flash drive connected. Warning message is shown on the display.
Connect or check the USB flash drive. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 734
Update file not recognised or not present. Warning message is shown on the display.
Check update file (e.g. for correct file name). If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 735
Update file does not match the device, update file too old. Warning message appears on the display, update process is interrupted.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 736
Write or read error occurred. Warning message is shown on the display.
Check USB flash drive and the data contained on it or replace USB flash drive.Never unplug a USB flash drive if the ‘Data Transmission’ LED is still flashing or lit. If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 737
File could not be opened. Warning message is shown on the display.
Remove and then reinsert USB flash drive; check or replace USB flash drive
STATE 738
Log file cannot be saved (e.g. USB flash drive is write protected or full). Warning message is shown on the display.
Create storage space, remove write protection, check or replace USB stick if necessary.If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 740
Initialisation error-error in file system on USB flash drive. Warning message is shown on the display.
Check USB flash drive; reformat on PC for FAT12, FAT16 or FAT32.
STATE 741
Error during recording of logging data. Warning message is shown on the display.
Remove and then reinsert USB flash drive; check or replace USB flash drive
STATE 743
Error occurred during the update process. Warning message is shown on the display.
Repeat the update process, check the USB stick. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 745
Update file is corrupt. Warning message appears on the display, update process is interrupted.
Re-download update file. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 746
Error occurred during the update process. Warning message appears on the display, update process is interrupted.
Wait for 2 minutes, then start the update again. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 751
Time lost. Warning message is shown on the display
Reset the time and date on the inverter. Check update file (e.g. for correct file name). If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 752
Real Time Clock module communication error. Warning message is shown on the display.
Reset the time and date on the inverter. Check update file (e.g. for correct file name). If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 753
Internal error: Real Time Clock module is in emergency mode. Time may be inaccurate or lost (feeding energy into the grid normally).
Reset the time and date on the inverter. Check update file (e.g. for correct file name). If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 754-755
Provides information about the processor status. Warning message on the display.
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 757
Hardware error in the Real Time Clock module. Error message is shown on the display; the inverter is not feeding any energy into the grid.
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 758
Internal error: Real Time Clock module is in emergency mode.Time may be inaccurate or lost (feeding energy into the grid normally).
Reset time and date on the inverter
STATE 760
Internal hardware error. Error message is shown on the display.
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 761-765
Provides information about the internal processor status. Warning message is shown on the display.
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 766
Emergency power de-rating has been activated. Error message is shown on the display.
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 767
Provides information about the internal processor status. Warning message is shown on the display.
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 768
Different power limitations in the hardware modules. Warning message is shown on the display.
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 772
Storage unit not available. Warning message is shown on the display.
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 773
Software update group 0 (invalid country setup). Warning message is shown on the display.
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 775
PMC power stage set not available. Warning message is shown on the display.
Press ‘Enter’ key to acknowledge error. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 776
Invalid device type. Warning message is shown on the display.
Press ‘Enter’ key to acknowledge error. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 781-794
Provides information about the internal processor status. Warning message is shown on the display.
If STATE code is displayed all the time contact your local Fronius Service Partner.
fronius galvo inverter

Fronius GALVO Inverter Error Codes

The Fronius Galvo is a high frequency transformer, single-phase inverter available in power categories from 1.5 to 3.1 kW.

Fronius Galvo STATE codes beginning with 1xx

Error Code Description of Error What to Do
STATE 102
The AC voltage is too high. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 103
The AC voltage is too low. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 105
AC frequency is too high. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 106
The AC frequency is too low. Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 107
AC grid outside the permissible limits.Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.
STATE 108
Stand alone operation detected.Following careful testing and when the grid conditions are within the permissible range again, the inverter will resume feeding energy into the grid.
Check grid connections: If this STATE code keeps recurring, contact your solar power system installer.

Fronius Galvo STATE codes beginning with 3xx

Error Code Description of Error What to Do
STATE 301
Overcurrent (AC). Short-term interruption while feeding energy into the grid due to over current in the inverter.The inverter resumes with its startup routine.
Fault is rectified automatically. If this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 302
Safety circuit detects a current peak on the PV generator side. Short-term interruption while feeding energy into the grid due to over current in the inverter.The inverter resumes with its startup routine.
Fault is rectified automatically. If this STATE code is displayed all the time: notify your local Fronius service partner.
STATE 303
Power stage set over temperature. Short term interruption while feeding energy into the grid due to over temperature.The inverter resumes with its startup routine.
Purge openings for cooling air and heat sink if necessary; fault is rectified automatically. If this STATE code keeps recurring contact your solar power system installer
STATE 304
Internal temperature is too high. Short term interruption while feeding energy into the grid due to over temperature.The inverter resumes with its startup routine.
Purge openings for cooling air and heat sink if necessary; fault is rectified automatically. If this STATE code keeps recurring contact your solar power system installer.
STATE 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 startup routine.
Fault is rectified automatically; if this STATE code occurs when there is sufficient insolation (sunlight) contact your solar power system installer.IMPORTANT! Due to the low level of insolation (sunlight) early in the morning and in the evening, the STATE codes 306 (LOW PV OUTPUT) and 307 LOW PV VOLTAGE) are displayed routinely at these times of day. These STATE codes do not indicate any kind of fault.
STATE 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 startup routine.
Fault is rectified automatically; if this STATE code occurs when there is sufficient insolation (sunlight) contact your solar power system installer.IMPORTANT! Due to the low level of insolation (sunlight) early in the morning and in the evening, the STATE codes 306 (LOW PV OUTPUT) and 307 LOW PV VOLTAGE) are displayed routinely at these times of day. These STATE codes do not indicate any kind of fault.
STATE 308
Intermediate circuit. Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine overvoltage
Fault is rectified automatically. If this STATE code is displayed all the time, notify your local Fronius service partner.
STATE 309
DC input voltage too high.Short term interruption while feeding energy into the grid. The inverter resumes with its startup routine.
Fault is rectified automatically. If this STATE code is displayed all the time, notify your local Fronius service partner.

Fronius Galvo STATE codes beginning with 4xx

Error Code Description of Error What to Do
STATE 401
No communication with the power stage set possible. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 406
Power stage set temperature sensor faulty. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 407
Internal temperature sensor faulty. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 408
DC feeding into the grid detected. The inverter will automatically attempt to connect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 412
Fixed voltage mode has been selected instead of MPP voltage mode and the fixed voltage has been set to too low or too high a value
If this STATE code persists contact your solar power system installer.
STATE 415
Safety cut out via option card or RECERBO has triggered. The inverter is not feeding any energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 416
No communication possible between power stage set and control system. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 425
No communication possible with the power stage set. The inverter will automatically attempt to reconnect again and, if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 445
Invalid limit value settings.The inverter is not feeding any energy into the grid for safety reasons.
Update the inverter firmware with the latest firmware here. If the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 452
Communication error between the processors. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time, notify your local Fronius Service Partner.
STATE 453
Short term grid voltage error. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time, notify your local Fronius Service Partner.
STATE 454
Short term grid frequency error. The inverter will automatically attempt to connect again, and if possible, will resume feeding energy into the grid.
If the STATE code is displayed all the time, notify your local Fronius Service Partner.
STATE 457
Grid relay sticking. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 459
Error when recording the measuring signal for the insulation test.The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 460
Reference voltage source for the digital signal processor (DSP) is working out of tolerance. The inverter is not feeding any energy into the grid.
Contact your local Fronius Service Partner.
STATE 472
Fuse for solar panel ground is faulty.The inverter is not feeding any energy into the grid.
Replace fuse for solar panel ground; if this STATE code keeps recurring contact your solar power system installer.
STATE 475
Solar panel ground, insulation fault (connection between solar panel and ground).The inverter is not feeding any energy into the grid.
If this STATE code keeps recurring, contact your solar power system installer
STATE 482
Startup incomplete. The inverter is not feeding any energy into the grid.
Perform AC reset (turn AC circuit breaker off and on), complete startup.

Fronius Galvo STATE codes beginning with 5xx

Error Code Description of Error What to Do
STATE 502
Insulation error on the solar panels. Warning message is shown on the display.
If this STATE code keeps recurring, contact your solar power system installer.
STATE 509
No energy fed into the grid in the past 24 hours. Warning message is shown on the display.
It is normal to see the state 509 code when the inverter has just been installed.Acknowledge STATE code; check whether all the conditions for the problem free feeding of energy into the grid have been met. If the STATE code is displayed all the time: look out for further STATE codes.
STATE 516
Firmware fault with the inverter, firmware update required.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 517
Derating caused by too high a temperature. When power derating occurs, a warning message is shown on the display.
Purge cooling air openings and heat sink if necessary; fault is rectified automatically; if this STATE code keeps recurring contact your solar power system installer.
STATE 551
Fuse for the solar panel ground is faulty. Warning is shown on display.
Replace fuse for solar panel ground; if this STATE code keeps recurring contact your solar power system installer.
STATE 558
Functional incompatibility (one or more PC boards in the inverter are not compatible with each other, e.g. after a PC board has been replaced).Possible error displays or malfunction on the inverter.
If this STATE code keeps recurring contact your solar power system installer.
STATE 560
Derating caused by over-frequency. This STATE code is displayed when the grid frequency becomes excessively high. The inverter will then reduce its output. The status indicator will continue to be displayed until the inverter has returned to normal operation.
As soon as the grid frequency is back within the permissible range and the inverter has returned to normal operation, the fault is rectified automatically. If this STATE code keeps recurring contact your solar power system installer.
STATE 567
Grid Voltage Dependent Power Reduction is active. This state code is a warning informing you that the Grid Voltage Dependent Power Reduction mode (GVDPR or Volt – Watt mode) has been activated and the inverter will continue to operate with reduced power output. This is because the grid voltage has exceeded 250Vac and the GVDPR has been enabled to try to reduce the voltage rise at the inverters terminals. This mode must be enabled by default in accordance with the latest Australian Standards
Acknowledge status code; if the STATE 567 code keeps recurring contact your local solar power system installer.
STATE 568
Incorrect input signal on the multifunction current interface. The STATE code is displayed in the case of an incorrect input signal on the multi-function current interface and with the following setting: Basic menu / Input signal / Mode of operation = Ext. Signal, triggering method = Warning
Acknowledge status code; check the devices connected to the multi-function current interface; if this STATE code keeps recurring contact your solar power system installer.

Fronius Galvo STATE codes beginning with 6xx

Error Code Description of Error What to Do
STATE 668
Incorrect input signal on the multi-function current interface. The inverter is not feeding any energy into the grid. The STATE code is displayed in the case of an incorrect input signal at the multi-function current interface and with the following setting:Basic menu / Input signal / Mode of operation = Ext. Signal, triggering method = Ext. Stop
Check the devices connected to the multi-function interface. If this STATE code keeps recurring, notify your local Fronius service partner.

Fronius Galvo STATE codes beginning with 7xx

Error Code Description of Error What to Do
STATE 705
Conflict when setting the inverter number (e.g. number already assigned).
Correct the inverter number via the setup menu.
STATE 721
EEPROM has been reinitialised or EEPROM is faulty. Warning message is shown on the display.
Acknowledge STATE code. If the STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 731
Initialisation error – USB stick is not supported. Warning message is shown on the display.
Check or replace the USB stick. Check the file system on the USB stick. If the STATE code is displayed all the time, notify your local Fronius Service Partner.
STATE 732
Over current on USB stick. Warning message is shown on the display.
Check or replace the USB stick. Check the file system on the USB stick. If the STATE code is displayed all the time, notify your local Fronius Service Partner.
STATE 733
No USB stick connected. Warning message is shown on the display.
Connect or check the USB stick. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 734
Update file not recognised or not present. Warning message is shown on the display
Check update file (e.g. for correct file name). If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 735
Update file does not match the device, update file too old. Warning message appears on the display, update process is interrupted.
Update the inverter firmware; if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 736
Write or read error occurred. Warning message is shown on the display.
Check USB stick and the data contained on it or replace USB stick.Never unplug a USB stick if the ‘Data Transmission’ LED is still flashing or lit. If the STATE code is displayed all the time, contact your local Fronius Service Partner.
STATE 738
Log file cannot be saved (e.g. USB stick is write protected or full). Warning message is shown on the display.
Create storage space, remove write protection, check or replace USB stick if necessary.If STATE code is displayed all the time contact your local Fronius Service Partner.Create storage space, remove write protection, check or replace USB stick if necessary.If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 743
Error occurred during the update process. Warning message is shown on the display.
Repeat the update process, check the USB stick. If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 745
Update file is corrupt. Warning message appears on the display, update process is interrupted.
Re-download firmware, if the STATE code is displayed all the time after the firmware update contact your local Fronius Service Partner.
STATE 751
Time lost. Warning message is shown on the display.
Reset the time and date on the inverter. Check update file (e.g. for correct file name). If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 752
Real Time Clock module communication error. Warning message is shown on the display.
Reset the time and date on the inverter. Check update file (e.g. for correct file name). If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 757
Hardware error in the Real Time Clock module. Error message is shown on the display; the inverter is not feeding any energy into the grid.
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 758
Internal error: Real Time Clock module is in emergency mode. Time may be inaccurate or lost (feeding energy into the grid normally).
If STATE code is displayed all the time contact your local Fronius Service Partner.
STATE 766
Emergency power de-rating has been activated. Error message is shown on the display.
If STATE code is displayed all the time contact your local Fronius Service Partner.

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