Lost the WiFi connection on your Sungrow inverter? It happens more often than you’d think. A power outage, a modem restart, or even a firmware update can drop the connection between your inverter and your home network.
The good news is that reconnecting a Sungrow inverter to WiFi is straightforward. This guide covers all current WiFi-enabled Sungrow models, including the SG-D, SG-KTL-M, SG-K-20 Hybrid, and the newer SH series hybrid inverters.
Why Your Sungrow Inverter Disconnects from WiFi
Before you start troubleshooting the connection, it helps to know what caused the dropout. Most WiFi disconnections come down to one of these causes.
- A power outage or blackout reset the inverter
- Your modem was restarted, replaced, or upgraded by your internet provider
- You changed your WiFi password or switched internet providers
- The solar system was switched off at the isolator for maintenance or electrical work
- An electrician worked on the switchboard or circuits and toggled the solar supply
- The inverter’s WiFi dongle lost its connection settings after a firmware update
- Your modem was moved further from the inverter, weakening the signal strength
If any of these happened recently, there’s a good chance your Sungrow inverter just needs to be reconnected to your home WiFi network.
Before you start: Your inverter is still generating power even when WiFi is disconnected. The WiFi connection is only used for monitoring and reporting. Your solar system continues to produce electricity and feed it into your home and the grid without an active WiFi connection.
What You’ll Need
Gather these before you start so the process goes smoothly.
- A smartphone or tablet with WiFi capability
- The iSolarCloud app installed (available on Google Play and Apple App Store)
- Your iSolarCloud account login details
- Your home WiFi network name (SSID) and password
- Access to the inverter (usually mounted on a garage wall or outside near the meter box)
If you don’t have an iSolarCloud account yet, you can create one in the app. You’ll need the serial number from your inverter’s label to register your system.
Step 1: Connect Your Device to the Inverter’s WiFi
Your Sungrow inverter broadcasts its own WiFi network that you’ll connect to first. This is a direct connection between your phone and the inverter, separate from your home WiFi.
- Open Settings on your smartphone or tablet
- Go to WiFi Settings
- Look for a network named “SG-“ followed by your inverter’s serial number (e.g., SG-A1234567890)
- Connect to this network. The default password is usually sg12345678 (check the label on your inverter if this doesn’t work)
- Wait for the connection to confirm. Your phone may warn you that this network has no internet access. That’s expected and normal, so stay connected to it
You need to be standing within about 5 metres of the inverter for this step. The inverter’s WiFi signal is low-powered and doesn’t reach far.
Can’t see the inverter WiFi? Check that the WiFi dongle is firmly plugged into the inverter. The dongle is a small USB-style device plugged into the bottom or side of the unit. Try unplugging it, waiting 30 seconds, and reinserting it. The inverter WiFi network should appear within a minute or two.
Step 2: Log In and Open WLAN Configuration
With your device connected to the inverter’s WiFi, open the iSolarCloud app.
- Log in to your iSolarCloud account with your email and password
- Tap the More tab in the bottom navigation bar
- Select WLAN Configuration from the menu
- The app will detect that you’re connected directly to the inverter and display a confirmation message
- Tap Next to proceed to the network selection screen
If the app doesn’t detect the inverter, go back to your phone’s WiFi settings and make sure you’re still connected to the inverter network (the “SG-” network), not your home WiFi. Some phones automatically switch back to known networks with internet access.
Step 3: Connect to Your Home WiFi Network
This final step links the inverter to your home network so it can send monitoring data to Sungrow’s cloud servers.
- A list of available WiFi networks will appear on screen
- Select your home WiFi network from the list
- Enter your WiFi password carefully (it’s case-sensitive)
- Tap Next or Connect
- Wait for the confirmation screen. A green checkmark or success message confirms the inverter has connected to your network
- Your phone will now disconnect from the inverter WiFi. Reconnect to your home WiFi as normal
It can take up to 10 minutes for your monitoring data to start appearing in the iSolarCloud app after reconnection. If you don’t see updated data after 30 minutes, try the process again from Step 1.
Troubleshooting Common Issues
If the steps above didn’t work, try these fixes before calling your installer.
Inverter WiFi Network Not Showing Up
- Check that the WiFi dongle is firmly plugged into the inverter
- Remove the dongle, wait 30 seconds, and reinsert it
- Make sure the inverter is powered on (the screen should be active during daylight hours)
- Stand within 5 metres of the inverter when scanning for networks
- Try turning your phone’s WiFi off and on again to force a fresh scan
Connection Fails at Step 3
- Double-check your WiFi password for typos
- Make sure your home WiFi is broadcasting on the 2.4GHz band. Most Sungrow WiFi dongles don’t support the 5GHz band
- If your modem uses a combined 2.4/5GHz network, check the modem settings and enable the 2.4GHz band separately
- Move your modem closer to the inverter if possible, or set up a WiFi range extender
- Check that your modem doesn’t have MAC address filtering enabled, which can block new devices
Connected but No Data in the App
- Wait at least 30 minutes. Data sync can be slow after a fresh reconnection
- Check that your inverter firmware is up to date through the iSolarCloud app
- Log out of the app and log back in to refresh your session
- Make sure the inverter serial number registered in the app matches the label on the physical unit
- If the problem continues for more than a day, the dongle itself may need replacing
Tips for a Stable WiFi Connection
A few simple habits can help prevent future WiFi dropouts and keep your monitoring running smoothly.
- Keep your modem within reasonable range of the inverter. WiFi signals weaken through walls, metal sheeting, and distance
- If your modem is far from the inverter, install a dedicated WiFi range extender near the inverter’s location
- After any power outage, check the iSolarCloud app within a day to confirm the inverter reconnected automatically
- When you change your WiFi password, reconnect the inverter straight away using the steps above
- Keep the iSolarCloud app updated on your phone for the latest compatibility and bug fixes
When to Call a Professional
If you’ve worked through every step above and your Sungrow inverter still won’t connect, the issue might be hardware-related. A faulty WiFi dongle, a damaged antenna connection, or a firmware bug can all prevent the inverter from joining your network.
At SolaXs, we service and maintain solar systems across the Mid North Coast, including Port Macquarie and surrounding areas. With over 25 years of experience, we can diagnose WiFi dongle faults, replace hardware, and get your monitoring back online quickly.
Contact us to book a service call or get help with your Sungrow inverter.
When to Call a Professional About Your Sungrow Inverter
WiFi connectivity issues are usually straightforward to fix yourself. However, some situations point to a deeper problem that needs a qualified technician rather than another round of troubleshooting.
Contact a professional if you notice any of the following:
- The inverter repeatedly drops off WiFi within minutes of reconnecting
- Error codes appear on the Sungrow display alongside the connectivity issue
- Your system’s energy production has dropped noticeably, even on clear days
- The inverter firmware is outdated and the iSolarCloud app cannot update it remotely
- You have tried a factory reset and the dongle still fails to broadcast its network
On the Mid North Coast, humidity and salt air can affect hardware over time, including WiFi dongles. Our team at SolaXs services Sungrow systems regularly across Port Macquarie and surrounding areas. If basic troubleshooting has not resolved your issue, book a service call and we will get your monitoring back online. Reliable WiFi monitoring means you catch performance drops early, which protects your investment over the long run.
Troubleshooting Common WiFi Connection Issues
Even after following the setup steps, WiFi dropouts happen. Most connection problems come down to signal strength, router settings, or firmware.
- Weak signal: If the inverter is more than 10 metres from the router or separated by thick walls, the connection will drop. A WiFi extender or powerline adapter solves this.
- Router on 5GHz only: Most solar inverters only support 2.4GHz networks. Check your router settings and make sure the 2.4GHz band is enabled.
- Firmware out of date: Manufacturers push firmware updates that fix connectivity bugs. Check the Sungrow monitoring app for available updates.
- IP conflict: If another device on your network shares the same IP address, the inverter will lose connection. Setting a static IP for the inverter prevents this.
- Password changed: If you recently changed your WiFi password, the inverter will disconnect. You will need to re-enter the new password through the inverter menu.
If the connection drops repeatedly after trying these fixes, the WiFi module itself may be faulty. Contact SolaXs to arrange a replacement. On the Mid North Coast, we carry spare modules for all major brands and can usually swap them same-day.
For more information, see the Clean Energy Council solar inverter buyers guide and the Australian Government Small-scale Renewable Energy Scheme.