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If after changing modem the app FusionSolar show the message “Huawei Dongle Offline”, In most cases, this isn't a fault with the inverter. It simply means it has lost its Wi-Fi connection and needs to be connected to the new home network. The simplest procedure is to use WLAN Configuration directly from the FusionSolar app, without configuring anything from the browser.
What you will learn:
By the end of this guide you will know:
- why does the message appear Huawei Dongle Offline;
- what does this error really mean;
- How to reconnect Huawei inverter to Wi-Fi;
- what password to use during setup;
- what mistakes to avoid;
- How to check if everything is back online.
Index
What is the Huawei Dongle and Why Does It Appear Offline?
You changed your modem and from that moment the app FusionSolar show the message “Huawei Dongle Offline”? In practice it means that Huawei inverter lost Wi-Fi connection.
The message refers to the dongle, that is, the communication device installed on the inverter that allows it to connect to the Internet and send data to the FusionSolar app.
When the dongle can no longer communicate with the router, the inverter continues to produce energy normally, but production, consumption and statistics are no longer updated in the app.
This problem often occurs after:
- modem replacement;
- change the name of the Wi-Fi network;
- change Wi-Fi password;
- changing network security settings.
Fortunately, in most cases the solution only takes a few minutes.
My experience
This guide was born from a problem that was actually solved on my system.
After replacing the home modem, FusionSolar continued to show Offline Dongle and the inverter could no longer connect to the new Wi-Fi network.
I initially tried configuring it via browser, as suggested by many guides online, but to no avail.
The procedure described in this article is the one that actually solved the problem using only the app FusionSolar.
Why the browser often doesn't work
Many guides explain how to reconfigure the dongle using your smartphone's browser.
In my case this procedure proved to be complicated and unreliable.
The phone kept automatically switching to the data connection or the home Wi-Fi network, interrupting communication with the inverter.
For this reason I recommend using the function directly WLAN Configuration of the device present in the FusionSolar app.
Besides being simpler, it avoids many of the connection problems that can occur during setup.
Before you start
Before starting the procedure, check these four points.
- The inverter must be turned on.
- You need to be near the inverter with your smartphone.
- Have your Wi-Fi network password available.
- If the router uses both the network 2.4 GHz be that one 5 GHz, make sure the network is 2.4 GHz is active, because it is the one generally used by the Huawei Smart Dongle.
How to reconnect your Huawei inverter to the new Wi-Fi
After changing your modem, the easiest way to restore the connection is to use the app directly. FusionSolar. There is no need to configure the dongle via browser: the procedure is WLAN Configuration of the device It's faster and more reliable.
1. Turn off mobile data
Before you begin, please completely disable the 4G/5G of the smartphone.
This way, your phone will communicate exclusively with the inverter during setup, preventing it from automatically switching to a data connection.
2. Open FusionSolar
Open the app FusionSolar.
Do not enter the system monitoring screen, but open the dedicated configuration function.
Path:
Services → WLAN Configuration
Once inside, select "Connect to another Wi-Fi network." You can then select the inverter or scan the QR code.
3. Scan the QR Code
Scan the QR Code on the Smart Dongle or on the inverter.
The app will automatically start the setup process.
4. Connect to the inverter network
When FusionSolar prompts you, connect to the Wi-Fi network generated by the inverter.
When prompted for your password, enter:
Changeme
Important: the C must be capitalized.
If Android displays the message:
This network does not have Internet access
select:
Stay connected
or
Connect only this once.
5. Access the inverter
Once the connection is established, FusionSolar will display the name of the inverter.
In my case it was:
SUN2000-BT2240102866
Awards Sign in.
Then enter the login password requested by the FusionSolar app.
6. Select your home Wi-Fi network
FusionSolar will display a list of available Wi-Fi networks.
Select your modem's network.
Enter your password.
Awards Connect.
The inverter will automatically save the new credentials and complete the connection.
If the connection fails
If the inverter fails to connect on the first attempt, check these points before repeating the procedure.
Check your Wi-Fi password
Check that you have entered your home network password correctly.
Check the 2.4 GHz network
Huawei Smart Dongle uses the network normally 2.4 GHz.
If the router only uses the network 5 GHz, the connection may fail.
Check the type of Wi-Fi security
In my case the router was configured with WPA3.
To allow the Smart Dongle to connect, I temporarily changed the network security setting WPA2, thus completing the configuration.
Note: This operation may not be necessary on all routers, but in my case it was indispensable.
Mistakes to avoid
Avoid these common mistakes during setup:
- leave mobile data turned on;
- type changeme with a lowercase “c”;
- select a Wi-Fi network other than the one you want;
- entering an incorrect Wi-Fi password;
- use a network only 5 GHz if the router does not also offer the 2.4 GHz;
- Exit the procedure before FusionSolar completes the setup.
How to verify that the connection has been restored
Once setup is complete, the inverter will automatically use the new Wi-Fi network.
To verify that everything went well, check these signs:
- the app FusionSolar go back to update the system data;
- production and consumption are displayed normally;
- the message Offline Dongle disappears;
- The inverter LEDs return to normal operating state.
If all these checks are positive, the connection has been successfully restored.
FAQ - Frequently Asked Questions
Why does FusionSolar display “Huawei Dongle Offline”?
This means that the inverter's communication module can no longer connect to the Wi-Fi network. The inverter continues to produce power normally, but the app is no longer receiving data.
Do I have to use the browser?
In my case, no. The procedure was completed directly from the FusionSolar app by entering Services → WLAN Configuration.
What is the initial password of the Huawei dongle?
In my case the password required for the first connection was:
Changeme
with the capital C.
Do I need to change my router?
Not always.
In my case it was necessary to set the Wi-Fi security to WPA2, because with WPA3 the connection was not completed.
Can changing modems cause this problem?
Yes.
When the Wi-Fi network name or password changes, the Smart Dongle continues to search for the old connection and must be configured again.
In summary
The message Offline Dongle After changing the modem, it does not indicate a fault with the Huawei inverter.
In most cases, it is sufficient to reconfigure the Wi-Fi connection via FusionSolar, connect to the network generated by the Smart Dongle and enter the new home network credentials.
By following this procedure, you can quickly restore the connection and go back to monitoring production and consumption directly from the app.
Conclusion
Changing modems is one of the most common causes of lost connection between the Huawei inverter and FusionSolar.
Fortunately, the solution is much simpler than it seems and, in most cases, can be performed directly from your smartphone without resorting to advanced router configurations.
This guide is based on real-world experience and covers all the steps that allowed me to get my system back online after switching my Wi-Fi network. If you follow the procedure step by step, you can restore your connection in just a few minutes and resume monitoring your PV system normally.
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