APsystem ECU - Activate Connection

Communication Setup Overview​

While most inverters offer more straightforward connectivity through Modbus TCP or API integration, APsystems requires a more complex setup involving RS-485 communication and additional hardware configuration. This guide outlines the complete process.

APsystems inverters use RS-485 communication via RJ45. To connect to a network, a bridge device is needed to convert RS-485 to Modbus TCP. The Waveshare RS485 to ETH converter (RS232/485 to ETH-B) can be used for this purpose and is available from Waveshare directly.

Prerequisites​

  • Mobile device with EMA Manager  app installed from:
    • App Store  (iOS)
    • Play Store  (Android)
  • Access to the ECU  device
  • WiFi  connectivity
  • Waveshare RS485 to ETH converter or equivalent RS-485 to TCP bridge
  • RS-485 cable for connection between ECU and converter

Configuration Process​

Initial Connection​

  1. Press the AP  button on the ECU
  2. Connect to WiFi network: ECU_R_216xxxx
  3. Use password: 88888888

Modbus Configuration​

  1. Launch EMA Manager
  2. Navigate to: Local Access  → Workspace  → Sunspec Configuration
  3. Enable Modbus  toggle
  4. Save changes and acknowledge any warnings

Bridge Setup​

  1. Connect the RS-485 cable between your ECU's RS-485 port and the Waveshare converter
  2. Configure the converter's network settings according to your local network requirements
  3. Make note of the IP address assigned to the converter - you'll need this for testing and monitoring

Important Notes​

  • AP mode  remains active for 1 hour
  • Press AP  button again to extend configuration time
  • Your specific inverter IDs will differ from documentation examples
  • Ensure proper wiring between ECU and RS-485 converter
  • Keep the converter in a dry, protected location

Testing Connectivity​

After configuring both the ECU and the RS-485 to TCP bridge, you should verify that the connection is working properly. You can follow our testing guide to confirm the connection. When testing APsystems ECU devices through the bridge, remember that the default Modbus port is 502, and the Unit ID is typically set to 1. You may need to wait a few minutes after configuration before the Modbus TCP connection becomes active. When testing, use the IP address of your RS-485 to TCP bridge, not the ECU's IP address.

Troubleshooting​

Connection Issues​

If unable to connect to ECU :

  1. Verify AP mode  is active
  2. Maintain close proximity to ECU  during setup
  3. Check WiFi password (eight 8s)

Application Issues​

If experiencing problems with the app:

  1. Verify connection to ECU  network
  2. Restart EMA Manager
  3. Update to latest version

Modbus Problems​

If Modbus is not functioning:

  1. Confirm Modbus  toggle is enabled
  2. Verify inverter IDs are visible
  3. Check RS-485 cable connections
  4. Verify bridge device network settings
  5. Test connection with monitoring system

Bridge Communication Issues​

If the RS-485 to TCP bridge isn't working:

  1. Check power supply to the converter
  2. Verify RS-485 cable connections and polarity
  3. Confirm network settings on the converter
  4. Test network connectivity to the converter's IP address

Source​

Still need help? Contact Us Contact Us