To reset a Sungrow inverter, turn off the AC isolator, then the DC isolator, wait 60 seconds, and switch them back on in reverse order.
That five-step process clears most temporary faults. But there are situations where a basic reset is not enough, where you need a factory reset through the inverter menu, or where the fault code is telling you something a reset will not fix. Knowing the difference saves you a service call.
This guide covers the standard reset procedure for Sungrow residential inverters (SG and SH series), what the most common error codes actually mean, and how to tell when a reset is pointless and you need an electrician instead.
When You Should Reset Your Sungrow Inverter
A reset is the right first step when your Sungrow inverter shows a fault that appeared suddenly without any physical cause. Grid outages, voltage fluctuations, and brief power interruptions are the most common triggers. The inverter disconnects from the grid as a safety measure, and sometimes it does not reconnect automatically once power stabilises.
On the Mid North Coast, storm season and hot afternoons cause grid voltage spikes that trip Sungrow inverters regularly. If your inverter was working fine yesterday and is showing a red light or error code today, a reset is worth trying before anything else.
- Red or orange fault light on the front panel
- Error code on the display (grid fault, isolation fault, or communication error)
- Zero output during sunlight hours with panels connected and no shading
- iSolarCloud app shows the system offline but your WiFi is working
- Inverter restarted after a blackout and has not reconnected to the grid
If the same fault keeps coming back after resetting, the issue is not a temporary glitch. Repeated faults point to a hardware problem, a wiring issue, or a grid voltage problem that needs professional diagnosis.
How to Reset a Sungrow Inverter in Five Steps
This process works for all current Sungrow residential inverters, including the SG series (string inverters) and SH series (hybrid inverters). It takes about two minutes and does not require any tools. Do this during daylight hours so the inverter receives DC input from your panels when it restarts.
- Turn off the AC isolator. This is the switch on or near your switchboard labelled “Solar” or “Inverter”. Flip it to the OFF position.
- Turn off the DC isolator. This is the rotary switch on the bottom or side of the inverter itself, or on a separate DC isolator box nearby. Turn it to OFF.
- Wait 60 seconds. This allows the inverter capacitors to fully discharge and the internal processor to clear any stored fault states. Skipping this wait is the most common reason a reset does not work.
- Turn the DC isolator back ON. Wait 5 seconds for the inverter screen to light up.
- Turn the AC isolator back ON. The inverter will run through its startup sequence, which takes 1 to 3 minutes. You will see the display cycle through checks before it begins exporting.
Order matters. Always switch off AC first, then DC. When turning back on, go DC first, then AC. This is the safe shutdown and startup sequence for all grid-tied inverters.
Once the inverter completes its startup, check the display or your iSolarCloud app to confirm it is generating power. A successful reset will show a green light and active wattage output within a few minutes. If you see the same error code reappear, try the hard reset below.
How to Factory Reset a Sungrow Inverter
A factory reset restores the inverter to its original settings through the onscreen menu. This is more aggressive than a power cycle and will clear any custom settings your installer programmed, including export limits, grid voltage thresholds, and time-of-use schedules. Only do this if a standard power cycle reset did not clear the fault.
Sungrow Inverters With a Touchscreen (SH Series)
- On the inverter display, tap Settings
- Enter the installer password (default is 0000 on most units, though your installer may have changed it)
- Navigate to System Settings > Factory Reset
- Confirm the reset when prompted
- The inverter will restart automatically
Sungrow Inverters With Button Navigation (SG Series)
- Press the Enter button to access the menu
- Use the arrow buttons to navigate to Settings
- Select Factory Reset and confirm
- The inverter will restart and reconfigure
After a factory reset, your inverter will need to be reconfigured by your installer if custom grid settings or export limits were applied. On the Mid North Coast, most Essential Energy connections require specific export limit settings. If your system was set up by SolaXs, call the team and they can reconfigure remotely or send someone out.
Sungrow Error Codes That a Reset Will Fix
Not every error code responds to a reset. Some are temporary faults that clear on restart. Others indicate hardware problems that will come straight back. Here is what the most common codes mean and whether resetting is worth trying.
| Error Code | Meaning | Reset Likely to Fix? |
|---|---|---|
| 010 | Grid connection lost | Yes, if power has been restored |
| 002 | Grid overvoltage | Sometimes, if voltage has stabilised |
| 003 | Grid undervoltage | Sometimes, if voltage has stabilised |
| 006 | Grid frequency out of range | Yes, usually after brief outage |
| 012 | Leakage current too high | Rarely, usually indicates wiring issue |
| 039 | ISO fault (insulation resistance) | Rarely, check panels for water ingress |
| 041 | Leakage current sensor fault | No, hardware issue |
| 056 | GFCI device fault | No, needs professional inspection |
| 105 | Fan fault | No, fan may need replacement |
Codes in the 002-010 range are almost always grid-related and typically clear after a reset once the grid stabilises. Codes in the 012-056 range relate to insulation and grounding, and these need investigation even if a reset temporarily clears them.
If you are not sure what an error code means, take a photo of the display and send it to your installer. The inverter display guide covers how to interpret what your screen is showing.
When Resetting Your Sungrow Inverter Will Not Help
A reset fixes software glitches and temporary faults. It does not fix physical problems. If any of these apply, skip the reset and call your installer or a CEC-accredited electrician.
- Burn marks or melted plastic on the inverter or DC isolator. Turn everything off and do not touch it.
- Water inside the inverter enclosure. Sungrow units are IP65 rated, but failed seals or damaged conduit entries can let water in.
- Same error code returns within minutes of resetting. A persistent fault means the underlying cause has not been resolved.
- No display at all. If the screen is completely blank with all isolators on, the inverter may have an internal power supply failure.
- Crackling, buzzing, or unusual smells. These indicate electrical arcing or component failure. Switch off and call your installer immediately.
Your Sungrow inverter warranty is typically 10 years for residential units. If the inverter is still under warranty, contact your installer first rather than Sungrow directly, as the installer handles the warranty claim process.
Preventing Faults Before They Happen
Most Sungrow inverter faults are caused by external factors rather than the inverter itself. Grid instability, loose connections that develop over time, and environmental factors are the usual suspects. A few simple checks keep the reset count low.
- Check your iSolarCloud app weekly. Dropping output over weeks can signal a developing issue before a fault code appears.
- Keep the inverter ventilated. Sungrow inverters throttle output when they overheat. Make sure nothing is blocking the vents or stored against the unit.
- Inspect DC isolators annually. Water ingress into the DC isolator is a common cause of insulation faults, especially in coastal areas.
- Watch for grid voltage issues. If your inverter trips on overvoltage (error 002) regularly, your local grid voltage may be running high. Your installer can adjust the voltage trip settings within allowable limits, or lodge a complaint with your network provider.
An annual system inspection catches most problems before they cause downtime. SolaXs offers a Solar Care Plan that includes yearly inspections, priority service, and monitoring for Mid North Coast installations. Worth considering if you want someone keeping an eye on things so you do not have to.
When in Doubt, Start With a Reset
Most Sungrow inverter faults clear with a simple AC-off, DC-off, wait, DC-on, AC-on power cycle. It takes two minutes and fixes the majority of temporary glitches caused by grid instability. If the fault comes back, check the error code table above before calling anyone.
If you have a Sungrow inverter on the Mid North Coast and need help with a persistent fault, get in touch with the SolaXs team. With 25 years of experience installing and servicing solar systems from Port Macquarie to Coffs Harbour, they have seen every Sungrow error code there is.