Sungrow Inverter Not Responding? How to Reset It

Quick answer

Sungrow’s user manuals document the restart directly: if the inverter misbehaves, disconnect and reconnect the DC switch and the AC main switch. In practice that means switching the AC isolator off, then the DC isolator off, waiting one to two minutes until every light and the display are dark, then switching the DC isolator on (wait about five seconds) followed by the AC isolator. A steady green power light within a few minutes means the inverter is generating again.

When a reset is the right move

Try a reset when the LCD is frozen, the iSolarCloud app has stopped updating, a minor fault code has appeared, or the inverter sits in standby or an error state in good sunlight. Sungrow’s manuals also cover a software-level stop: you can set the inverter to OFF through the LCD menu or the app (a manual stop that halts the internal DSP), and restart it the same way — but that only helps if the display and controls are responsive. A full power cycle is the reset that clears deeper lockups.

One documented case from the manual: if the inverter stays in standby for more than ten minutes in daylight, check that sunlight is sufficient and the PV connections are correct — and if nothing is visibly wrong, disconnect and reconnect the DC switch and the main switch to restart. If it still does not work, the manual says to contact Sungrow.

Full reset: the documented power cycle

This applies to the Sungrow SG series (RS, RT, and CX families). Perform the reset during daylight — the inverter needs solar input to power back up.

1. Turn off the AC isolator. Use the Solar Supply Main Switch or the AC isolator near your switchboard or the inverter. Switch it to OFF.
2. Turn off the DC isolator. This is the PV Array DC Isolator, found under or beside the inverter. Switch it to OFF.
3. Wait one to two minutes. Every light and the display must go completely dark. This pause lets the internal capacitors discharge so the system resets fully.
4. Turn the DC isolator on and wait about five seconds.
5. Turn the AC isolator on.
6. Let the inverter boot. It runs internal checks and re-initializes communication. Within a few minutes the display or LEDs should show normal operation — a green power light means it is generating, and a solid blue NET/WLAN light means the Wi-Fi has reconnected.
7. Verify in iSolarCloud. Open the app and confirm that power generation and communication data are updating. If a warning or fault reappears, write down the exact fault code before contacting your installer or Sungrow support.

What the lights tell you afterward

• Green power light on — the inverter is running and generating. This is the normal state in daylight.
• Display or LEDs cycling, then settling — normal startup behavior; give it several minutes.
• Red indicator or an Error code on the LCD — a fault is active. Note the code; the manual lists recovery behavior per code, and many faults auto-recover once the cause clears. The recovery time can be adjusted in the app.
• Nothing lights up — check that the DC isolator is truly on, that it is daylight, and that no string breaker has tripped.

When to call a professional

Sungrow’s manuals consistently end troubleshooting sections with the same instruction: if the problem persists after a restart, contact your installer or Sungrow. Call a professional if:

• The same fault code returns after a proper power cycle.
• The inverter will not power up in good daylight with both isolators on.
• You see or smell anything wrong — heat discoloration, melted connectors, a burning smell — or any isolator looks damaged. Never restart into visibly damaged equipment or during a lightning storm.
• The inverter is part of a hybrid system and the battery behaves abnormally (error states, no charge/discharge) — battery issues need qualified diagnosis.
• You need to change grid, safety, or export settings, which require installer access.

Frequently asked questions

Will a reset delete my Sungrow settings or generation history?

No. A power cycle preserves your configuration and your energy records. The iSolarCloud app keeps your historical data in the cloud, and the inverter retains its settings locally. Only a deliberate factory reset — an installer-level action — would change configuration.

My Sungrow inverter shows nothing at night. Is that normal?

Yes. Without sunlight there is no DC power, so the inverter enters standby and the display and communication module shut down. This is expected behavior, not a fault. Perform any reset or troubleshooting during daylight hours.

How long should I wait before switching back on?

Wait until every light and the display are fully dark — at least one to two minutes. Switching back on too quickly can prevent the internal capacitors from discharging, and the reset may not take effect. Avoid multiple rapid restarts; always allow the full pause between shutdown and startup.

The app stopped updating but the inverter looks fine. Should I reset it?

A single power cycle is a reasonable first step because it also re-initializes the communication module. But if the inverter’s own lights show normal generation, the problem is more likely the Wi-Fi link or router — check those before assuming the inverter needs repeated resets, and note any fault code if one appears.