Sungrow Inverter and Battery Fault Codes in Australia
Updated 9 September 2026 · By SolarNevs Research Desk, Dealer surveys + verified sources · 1 source · Method ↗
Key Takeaways
- Many Sungrow fault codes, particularly those related to grid conditions, are temporary and the inverter will often self-recover.
- Codes like 039 (insulation resistance) and 088 (arc fault) indicate serious safety risks and require immediate professional attention from a CEC-accredited installer.
- Battery-specific faults (7xx, 8xx, 9xx series) often point to communication issues with the Battery Management System (BMS) or environmental factors like temperature.
- You can safely check basic items like circuit breakers, app notifications, and inverter display messages, but any work involving opening the inverter, DC wiring, or grid protection settings must be performed by a licensed technician.
Understanding Sungrow Inverter and Battery Fault Codes
When your Sungrow solar inverter displays a fault code or an alarm appears in your iSolarCloud app, it indicates that the system has detected a condition outside its normal operating parameters. These codes are designed to help you and your installer understand what is happening with your solar power system, ranging from temporary grid disturbances to critical hardware issues.
This guide, based on an Australian installer's compilation, explains common Sungrow inverter and battery fault codes you might encounter in Australia, what they mean, and the appropriate steps to take.
How Sungrow Inverters Detect and Report Faults
Sungrow inverters continuously monitor various electrical and environmental parameters to ensure safe and efficient operation. This includes monitoring grid voltage and frequency, DC input from solar panels, internal temperatures, and communication with connected components like smart meters and batteries.
When a parameter deviates from its safe or expected range, the inverter triggers a fault or alarm code. These codes are displayed on the inverter's LCD screen (if equipped), sent to the iSolarCloud app, and logged for diagnostic purposes. Some faults, particularly those related to transient grid conditions, are self-clearing, meaning the inverter will automatically resume operation once the condition passes. Others, especially those indicating hardware failures or safety risks, require manual intervention or professional repair.
Sungrow Fault and Alarm Code Table
The following table, compiled by Australian installer PSW Energy, details common Sungrow fault and alarm codes, their meanings, and recommended actions.
Code | What it means | What to do |
|---|---|---|
002 | Grid over-voltage | The grid voltage exceeds the inverter’s upper protection limit. This is often caused by high network voltage during peak solar export. The inverter restarts automatically when voltage drops. If persistent, your installer can check the AC wiring gauge and length, adjust the volt-watt response settings, or request a Western Power network voltage assessment. |
003 | Transient over-voltage | A temporary voltage spike exceeding the inverter’s limit. The inverter recovers once the grid stabilises. If frequent, contact your installer to check for a nearby surge source or grid instability. |
004 | Grid under-voltage | The grid voltage is below the inverter’s lower protection limit. Check for a grid outage or tripped breakers. If the grid is live and the code persists, contact your installer to check AC connections. |
005 | Transient under-voltage | A temporary voltage dip below the permitted minimum. The inverter will self-recover. If frequent, contact your installer. |
006 | AC over-current | The AC output current exceeds the inverter’s rated limit. The inverter will resume once current drops below the protection value. If persistent, contact your installer to check AC wiring and connections. |
007 | Transient AC over-current | The inverter will self-recover. If frequent, contact your installer. |
008 | Grid over-frequency | The grid frequency exceeds the protection limit. The inverter will self-recover. If persistent, contact your installer to verify protection parameter settings. |
009 | Grid under-frequency | The grid frequency is below the protection limit. The inverter will self-recover. If persistent, contact your installer. |
010 | Islanding detected | The inverter has lost its connection to the grid. Check your switchboard for tripped breakers. Confirm whether there is an area outage on the Western Power outage map. Check that the Solar Supply Main Switch and inverter AC isolator are both turned on. If the grid is available and this code persists, check whether the AC cable is firmly connected and whether live and neutral are correctly wired. |
012 | Leakage current fault | Current is leaking to earth through the PV array or wiring. Contact your installer. This can be caused by a damp environment (the inverter may reconnect when conditions improve), or by damaged insulation on AC or DC cables. If the environment is normal and cables are intact, contact Sungrow. |
014 | Grid voltage out of range (10-minute average) | The average grid voltage has exceeded the permitted limit for an extended period. Similar to 002 but based on a sustained average. Your installer can adjust the volt-watt response settings or request a Western Power network assessment. |
015 | Grid voltage out of range (10-minute average, under-voltage variant) | Sustained low average grid voltage. Check for a partial grid fault. If persistent, contact your installer. |
019 | Transient grid frequency deviation | Short-term frequency disturbance. The inverter will self-recover. If frequent, contact your installer. |
021 | DC bus over-voltage | The internal DC bus voltage has exceeded the safe limit. Restart the inverter. If persistent, contact your installer. |
022 | High PV input voltage | The DC voltage from the solar panels exceeds the inverter’s maximum input limit. Contact your installer immediately. This should not occur in a correctly designed system. Do not restart without professional inspection. |
025 | Internal hardware fault | Restart the inverter. If persistent, contact Sungrow or your installer. The inverter may need replacement under warranty. |
035 | Internal communication failure | Restart the inverter. If persistent, contact your installer. |
036 | Radiator temperature too high | The inverter’s heatsink has exceeded the safe temperature limit. Check ventilation around the inverter. Clear debris, spider webs, or vegetation within 300mm of the heatsink fins. Check for alarm 070 (fan fault) in the app. Consider a shade hood if this occurs regularly. |
037 | Ambient temperature too high | The environment around the inverter is too hot. Improve ventilation or add shading. |
039 | Insulation resistance too low (ISO fault) | The insulation between the PV array and earth has dropped below the minimum threshold. Contact your installer. Do not restart without professional inspection. Common causes: moisture in a rooftop DC isolator or MC4 connector, damaged cable insulation, or a panel junction box fault. If it clears in dry weather but returns after rain, there is a water ingress point that needs to be found and sealed. Your installer should check whether the ISO resistance protection value is set appropriately for local regulations. |
040 | DC injection too high | Restart the inverter. If persistent, contact your installer. Check whether the AC cable is correctly connected and whether insulation between the ground cable and the live wire is normal. |
041 | Relay check failure | The internal relay self-test has failed. Restart the inverter. If persistent, the relay may need replacement. Contact your installer. |
042 | DSP/ARM communication failure | Restart the inverter. If persistent, the inverter likely needs a firmware update or hardware service. Contact Sungrow. |
046 | EEPROM read/write failure | Internal memory fault. Restart the inverter. If persistent, contact your installer. The control board may need replacement. |
070 | Fan anomaly | The cooling fan is not operating correctly. The inverter can continue running but may derate. Check whether the fan is physically obstructed. If clear and the alarm persists, the fan may need replacement. Contact your installer. |
088 | Arc fault detected (AFD/AFCI) | The inverter has detected a potential arc in the DC wiring. ⚠️ This is a potential fire risk. Contact your installer immediately. Check whether any DC cable is damaged, any connection terminal or fuse is loose, or any component is burnt. After inspection, reconnect DC power and clear the AFD fault via the LCD or iSolarCloud app. The inverter will not restart until the fault is manually cleared. |
514 | Meter communication abnormal | The inverter has lost communication with the Smart Energy Meter. Check whether the RS485 communication cable between the inverter and meter is securely connected. Check whether the meter’s power cable connections are correct. Check whether the cable direction (input/output) is correct. If the existing system is multi-inverter, check whether the rated power setting of each inverter is correct. If persistent, contact your installer. Note: without meter communication, the inverter cannot limit export or manage battery charging based on household consumption. |
515 | WiFi module communication failure | The inverter has lost communication with the WiFi dongle. Check the dongle is firmly plugged in. Try pressing the button on the dongle three times to reset it. The inverter continues to generate power; only monitoring is affected. |
548–563 | PV string abnormal (string 1–16 respectively) | Low or zero output from a specific string. Check whether the affected string’s panels are shaded, dirty, or sheltered. Check for abnormal ageing on older panels. If the panels are clean and unshaded, contact your installer to check the string wiring. |
703 | Low average battery voltage | The battery voltage has dropped below the minimum operating threshold. Contact your installer. The battery may have been deeply discharged or there may be a cell imbalance. Measure the voltage of each battery module to check for imbalance (greater than 0.5V difference indicates a problem). |
707 | Battery over-temperature | Check ventilation around the battery. Ensure nothing is blocking airflow. If installed in a non-ventilated space or in direct sunlight, the installation may need modification. Contact your installer. |
708 | Battery low temperature | The battery will resume operation when it warms up. Most lithium batteries will not charge or discharge below 0°C to 5°C. |
711 | Battery transient overvoltage | Contact your installer. Check module voltages for imbalance. If modules are balanced, the battery or BMS may need service. |
714 | BMS communication fault | The inverter has lost communication with the battery management system. Check the RJ45 communication cable between the inverter and battery. Verify the first two pins (CAN H and CAN L) are correctly connected. Try replacing the cable with a new CAT5 cable. If the cable is secure and the alarm persists, check whether BMS communication voltage is between 3.3V and 5.0V (licensed electrician only). If voltage is absent, the BMS or inverter communication port may need replacement. |
715 | Battery hardware overvoltage | Contact your installer. This is a hardware-level protection trigger. |
717 | BMS and battery fault | Combined communication and hardware issue. Contact your installer or Sungrow support. |
832 | FET fault / battery switch fault | The battery’s internal switching hardware has faulted. Contact Sungrow support. |
833 | Battery internal hardware fault | The battery needs service or replacement. Contact Sungrow support. |
835 | Battery short-circuit fault | ⚠️ Contact Sungrow support immediately. Do not restart without professional inspection. |
836 | Battery internal communication failure | Contact Sungrow support. |
933 | Battery over-temperature alarm (warning level) | The battery is running hot but has not reached the fault threshold. Improve ventilation. Monitor the alarm; if it escalates to a 7xx fault, contact your installer. |
934 | Battery low temperature alarm (warning level) | The battery will self-recover when ambient temperature rises. |
937 | Battery pack voltage unbalance | One or more battery modules have a different voltage from the others. Contact your installer to measure individual module voltages. |
964 | BMS internal alarm | The BMS has detected an internal anomaly. Contact Sungrow support. |
Backup overload | The load on your backup circuit exceeds the inverter’s backup output capacity. Reduce the load by turning off high-draw appliances (air conditioners, heaters, kettles, pool pumps). The SH-RT supports “100% unbalanced loads” across three phases, but total load per phase must still be within the rated backup capacity. |
System alarm: anomaly during storm/outage | The inverter detected an anomaly during a grid transition event. This can result in a brief loss of backup power (typically up to one minute) while the inverter restarts and re-enters backup mode. If backup power is lost for longer than two minutes, contact your installer. |
What You Can Check Yourself, and What Requires a Licensed Installer
Understanding the difference between what you can safely check and what requires a licensed professional is crucial for both safety and effective troubleshooting.
What you can check yourself:
- Inverter Display and App: Read the fault code or alarm message on your inverter's LCD screen or in the iSolarCloud app. This is your primary source of information.
- Circuit Breakers: Check your home's main switchboard for any tripped circuit breakers related to your solar system or household circuits.
- Grid Outages: Verify if there's a wider grid outage in your area using your electricity distributor's (e.g., Western Power) outage map.
- AC Isolator and Solar Supply Main Switch: Ensure both are in the 'ON' position.
- Shading and Debris: For PV string abnormal codes (548–563), check if solar panels are shaded, dirty, or covered by debris. For temperature alarms (036, 037, 707, 933), ensure the inverter and battery have clear ventilation and are not obstructed by vegetation or spider webs.
- WiFi Connection: For communication errors (515), check if the WiFi dongle is firmly plugged into the inverter and try resetting it by pressing its button three times. Ensure your home WiFi is operating on 2.4GHz, as Sungrow WiFi dongles operate on 2.4GHz only.
- Physical Connections (External): For meter (514) or BMS (714) communication faults, you can visually inspect the external communication cables (RS485 or RJ45) to ensure they are securely connected.
What requires a CEC-accredited installer or licensed electrician:
- Opening the Inverter Enclosure: Never open the inverter cover yourself. All work inside the inverter is restricted to licensed electricians under Australian electrical safety legislation.
- DC Wiring and Connectors: DC cables from solar panels carry dangerous voltage during daylight hours. Do not disconnect DC connectors or work on DC wiring.
- Insulation Resistance Faults (039): Diagnosing and fixing these faults, which can be caused by moisture in DC isolators or damaged cable insulation, requires specialised equipment and expertise.
- Arc Faults (088): These are a potential fire risk and require immediate professional inspection and repair.
- High PV Input Voltage (022): This indicates a potentially dangerous condition in the solar array and must be addressed by an installer.
- Grid Protection Settings: Adjusting inverter settings related to grid voltage or frequency limits (e.g., for codes 002, 008, 014) must be done by a qualified technician.
- Internal Hardware Faults (e.g., 025, 041, 046): These typically require replacement of components or the entire inverter.
- Measuring Voltages: Any measurement of internal voltages, such as BMS communication voltage or individual battery module voltages, must be performed by a licensed electrician.
- Firmware Updates: For RS and RT series, your installer can update firmware via the iSolarCloud app during a site visit. Legacy SG-D and SG-KTL-M series typically require a site visit with a USB dongle or direct connection.
What the Published Sources Do Not Tell You About Sungrow Faults
While the provided installer compilation offers practical advice for Sungrow fault codes, there are inherent limitations:
- Manufacturer's Official Documentation: This guide relies on an Australian installer's compilation (PSW Energy) rather than direct manufacturer documentation. While the installer states their list is "verified against current Sungrow Australia documentation," the primary manufacturer sources were not directly accessible for this compilation. This means specific technical details or alternative troubleshooting steps from Sungrow's own manuals might not be fully represented.
- Specific Model Scoping: The fault codes are presented generally for Sungrow inverters and batteries. The source does not explicitly detail if certain codes are exclusive to specific inverter models (e.g., SG-RS, SH-RT) or battery types, beyond the mention of the SH-RT supporting "100% unbalanced loads" for backup overload.
- Firmware Variations: Inverter behaviour and specific fault interpretations can sometimes vary slightly between different firmware versions. The compilation does not specify which firmware versions these codes apply to, meaning some nuances might exist for older or newer installations.
- Undocumented Codes: As with any complex electronic device, there may be rare or highly specific fault codes not covered in general compilations. If you encounter a code not listed here, always consult your installer or Sungrow support directly.
- Exact Numeric Thresholds: While codes like "Grid over-voltage" (002) are described, the exact voltage or frequency thresholds that trigger these alarms are not provided in this compilation. These thresholds are typically set according to local grid regulations and inverter specifications. ---
Frequently asked questions
What does Sungrow fault code 002 mean?
Sungrow fault code 002 indicates a grid over-voltage condition, meaning the grid voltage has exceeded the inverter’s upper protection limit. This is often caused by high network voltage during peak solar export and the inverter usually restarts automatically when the voltage drops.
What should I do if my Sungrow inverter shows an arc fault (088)?
An arc fault (code 088) is a serious safety issue indicating a potential fire risk. Do not attempt to restart the inverter yourself. Contact your CEC-accredited installer immediately for professional inspection and resolution.
Why is my Sungrow inverter showing a BMS communication fault (714)?
A BMS communication fault (code 714) means the inverter has lost communication with the battery management system. You can check the RJ45 communication cable between the inverter and battery for secure connection. If the issue persists, contact your installer.
Can I fix a Sungrow insulation resistance fault (039) myself?
No, an insulation resistance fault (code 039) requires a CEC-accredited installer. This fault indicates that the insulation between the PV array and earth has dropped below the minimum threshold, often due to moisture or damaged cabling, and requires professional diagnosis and repair.
My Sungrow inverter is offline but still generating power. What's wrong?
If your Sungrow inverter is generating power but offline, it likely has a WiFi module communication failure (code 515). This means the inverter has lost communication with its WiFi dongle. You can check if the dongle is firmly plugged in and try pressing its button three times to reset it. The inverter will continue to generate power, but monitoring will be affected.
References
- PSW Energy: Sungrow Alarm Codes — accessed 30 August 2026
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