SMA inverter
📋 Overview
The SMA inverter is connected to the Currentt Navigator to read production data and control the system.
⚙️ How does it work?
The Currentt Navigator communicates with the SMA inverter via Modbus TCP over the local network (Ethernet). SMA uses the SunSpec Modbus protocol — an industry standard for solar equipment. The Currentt Navigator reads production data, power levels and status information, and can control the inverter's power output.
🧰 Requirements
- Currentt Navigator (connected to the local network)
- Ethernet cable (RJ45, CAT5/Cat6)
- Laptop or smartphone (for accessing the inverter's web interface)
1️⃣ Step 1: Connect the inverter to the network
All current SMA inverters have a built-in Ethernet port (RJ45).
- Connect an Ethernet cable (RJ45) to the Ethernet port on the SMA inverter
- Connect the other end to your network switch or router
- The inverter automatically obtains an IP address via DHCP
2️⃣ Step 2: Determine the IP address
To configure the inverter, you need its IP address.
- Via your router: Check the DHCP client list for a device with "SMA" in the name
- Via the SMA WiFi AP: When the inverter is not connected via Ethernet, it broadcasts its own WiFi network (SSID: SMA_[serial_number]). Connect to it and navigate to 192.168.12.3
3️⃣ Step 3: Enable Modbus TCP
Modbus TCP is disabled by default on SMA inverters and must be enabled via the web interface.
- Open a browser and navigate to https://[IP address] of the inverter
- Accept the security warning (the inverter uses a self-signed certificate)
- Log in as Installer:
| Role | Default password |
|---|---|
| User | 0000 |
| Installer | 1111 (may have been changed by the installer) |
- Navigate to Device Parameters > External Communication > Modbus
- Set the following values:
| Setting | Value |
|---|---|
| Modbus TCP Server | Enabled |
| Port | 502 |
| Unit ID | 3 (default for SMA) |
- Save the settings
SMA uses a Unit ID which defaults to 3. The Modbus address entered in the Currentt Navigator is 123 + Unit ID. With the default Unit ID of 3, the Modbus address is 126.
The default installer password is 1111, but many installers change this during commissioning. Contact the installer if the password does not work.
4️⃣ Step 4: Configuration in the Currentt Navigator
After enabling Modbus TCP, the inverter must be added in the Currentt Navigator.
Via the Setup Wizard (recommended)
- Click the settings icon (top right of the screen)
- Choose Setup Wizard
- Follow the on-screen steps
Manual configuration
- Click the settings icon (top right of the screen)
- Go to Components
- Click the + button in the Inverters section
- Select SMA
- Enter the connection details:
| Parameter | Value |
|---|---|
| Connection | Modbus TCP |
| IP address | (IP address of the SMA inverter) |
| Port | 502 |
| Modbus address | 126 (default: 123 + Unit ID 3) |
📋 Settings summary
| Parameter | Value |
|---|---|
| Connection | Ethernet (Modbus TCP) |
| Protocol | SunSpec Modbus TCP |
| IP address | (dynamic or static) |
| Port | 502 |
| SMA Unit ID | 3 (default) |
| Modbus address | 126 (default: 123 + Unit ID) |
🛟 Troubleshooting
| Problem | Possible cause | Solution |
|---|---|---|
| No connection | Modbus TCP not enabled | Enable Modbus TCP via the inverter's web interface |
| No connection | Wrong IP address | Check the IP address via the router or web interface |
| No connection | Wrong port | Check that the port is set to 502 |
| No connection | Wrong Modbus address | Check the Modbus address: 123 + Unit ID (default Unit ID 3 → Modbus address 126) |
| No connection | Devices on different network | Ensure the Navigator and the SMA inverter are on the same (V)LAN |
| No connection after restart | IP address changed (DHCP) | Set a static IP address |
| Cannot access web interface | Unknown password | Contact the installer for the Installer password |
| Cannot change settings | Grid Guard code required | Some settings require a Grid Guard code — contact SMA or the installer |
✅ Compatible devices
Single-phase inverters (Sunny Boy)
| Model | Power |
|---|---|
| SB 3.0-1AV-41 | 3 kW |
| SB 3.6-1AV-41 | 3.6 kW |
| SB 4.0-1AV-41 | 4 kW |
| SB 5.0-1AV-41 | 5 kW |
| SB 6.0-1AV-41 | 6 kW |
Three-phase inverters (Sunny Tripower)
| Model | Power |
|---|---|
| STP 3.0-3AV-40 | 3 kW |
| STP 4.0-3AV-40 | 4 kW |
| STP 5.0-3AV-40 | 5 kW |
| STP 6.0-3AV-40 | 6 kW |
| STP 8.0-3AV-40 | 8 kW |
| STP 10.0-3AV-40 | 10 kW |
Single-phase hybrid inverters (Sunny Boy Smart Energy)
| Model | Power |
|---|---|
| SBS 3.6-10 | 3.6 kW |
| SBS 5.0-10 | 5 kW |
| SBS 6.0-10 | 6 kW |
Three-phase hybrid inverters (Sunny Tripower Smart Energy)
| Model | Power |
|---|---|
| STP SE 5.0-10 | 5 kW |
| STP SE 6.0-10 | 6 kW |
| STP SE 8.0-10 | 8 kW |
| STP SE 10.0-10 | 10 kW |