Connection Options
Option 1: Direct Ethernet Connection (Recommended)
This is the standard and best option for full functionality:
Connect an Ethernet cable from your inverter's internal LAN port to your home router
Modbus TCP is typically enabled by default on this port
Set a fixed IP address in your router for reliable connection
Provides complete functionality including control features
Option 2: WiNet-S Connection (Basic Functionality)
If you only need to read data:
Use your existing WiNet-S dongle that's already connected to iSolarFusion
Limited to read-only functionality
Sometimes requires manual Modbus activation (follow guide below)
If Modbus needs to be activated on your WiNet-S, follow these steps:
Finding Your WiNet-S Device
Option 1: Through Your Router (Easiest)
Log into your router
Look for a device named "espressif" in the connected devices list
Note down its IP address (it will look like 192.168.1.221)
Option 2: Through the iSolarFusion App
Open the iSolarFusion app on your phone
Tap the "Support" tab at the bottom
Tap "Local Access"
Follow the app's instructions to:
Scan the QR code on your WiNet-S dongle
Press the dongle button three times
Connect to the WiNet-S WiFi network
Accessing the WiNet-S Settings
Open your web browser (Chrome, Safari, etc.)
Type the IP address you found in the address bar
Example: http://192.168.1.221
Or: if you're at the phone standing just by your inverter (local access) the IP is http://11.11.11.1 but using a laptop/computer is recommended.
You'll see the WiNet-S login screen
Enter these login details:
Username: admin
Password: pw8888
Enabling Modbus TCP
After logging in, find and click "System" in the menu
Click "Transfer Configuration"
Look for the Modbus TCP settings
Switch on "Local Port" if it's not already enabled
Click "Save" or "Apply" (if available)
That's it! Your Modbus TCP is now enabled.
Testing Connectivity
Even though Modbus TCP sometimes comes enabled by default on Sungrow inverters, it's still important to verify that the connection is working properly. You can follow our testing guide to confirm the connection. For Sungrow inverters, use the default Modbus port 502. The Unit ID is typically set to 1. Testing the connection can help ensure that your network configuration is correct and that the inverter is properly accessible.
Common Problems and Solutions
Can't Find the IP Address?
Make sure your WiNet-S is properly inserted
Check if your phone/computer is connected to your home network
Try restarting your router
Login Not Working?
Double-check you're using: admin / pw8888
Make sure you're typing the password exactly as shown
If still not working, contact your installer
Can't Access the Web Page?
Verify you're connected to your home network
Try typing "http://" before the IP address
Try a different web browser
Need More Help?
If you're stuck:
Contact your installer
Have them enable Modbus access if needed
Keep note of any error messages you see
Extra Tips
The default login (admin/pw8888) is set by Sungrow. The user login is user/pw1111 but doesn't give modbus access.
Don't change any other settings unless you're sure
Save any changes you make
If something goes wrong, your installer can help reset everything