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Growatt Modbus RTU (RS-485)

✅ Compatible devices​

Single-phase inverters​

ModelPower
MIN 2500–6000TL-XH2.5 – 6 kW

Three-phase inverters​

ModelPower
MOD 3000–15000TL3-XH3 – 15 kW

Single-phase hybrid inverters​

ModelPower
SPH 3000–10000TL-BL-EU3 – 10 kW

Three-phase hybrid inverters​

ModelPower
SPA 4000–10000TL-BL-EU4 – 10 kW

🧰 Requirements​

  • Currentt Navigator Pro (with RS-485 Modbus connection)
  • RS-485 cable (twisted pair, e.g. CAT5 or a suitable 2-wire cable)
  • Phillips screwdriver (for access to the communication port)

⚠️ Safety warnings​

Note

Always switch off the inverter before making the communication connection. Set the DC switch to OFF and switch off the AC side via the distribution board.

1️⃣ Step 1: Switch off the inverter​

  1. Set the DC switch on the inverter to OFF
  2. Switch off the AC side via the distribution board (circuit breaker)
  3. Wait at least 5 minutes for the capacitors to discharge
  4. Check that the inverter display is off

2️⃣ Step 2: Connect the RS-485 cable​

The RS-485 port is located on the bottom of the Growatt inverter, near the communication ports.

  1. Remove the cover from the COM port on the bottom of the inverter
  2. Connect the RS-485 cable to the RS-485 terminals on the inverter:
TerminalSignalDescription
RS485-AData+Non-inverting (positive)
RS485-BData−Inverting (negative)
  1. Connect the other end to the RS-485 Modbus connection on the Currentt Navigator (A to A, B to B)
  2. Use a twisted pair cable for a reliable connection
  3. Replace the cover
Note

Ensure that the A and B connections are wired correctly. Swapping A and B will cause communication errors.

Ground connection

Connect the ground (GND) on one side only: either to the Currentt Navigator or to the device — but never on both sides. Connecting ground on both sides can cause a ground loop, leading to communication errors.

3️⃣ Step 3: Switch on the inverter​

  1. Switch on the AC side via the distribution board
  2. Set the DC switch on the inverter to ON
  3. Wait for the inverter display to start up

4️⃣ Step 4: Configure the inverter​

The communication settings are configured via the LCD display on the inverter.

  1. Navigate on the display to Settings
  2. Go to Communication Settings
  3. Set the following values:
SettingValue
Modbus address1 (default, adjust for multiple inverters)
Baud rate9600
ProtocolModbus RTU
  1. Confirm the settings
Multiple inverters

When using multiple Growatt inverters on the same RS-485 bus, each inverter must have a unique Modbus address (e.g. 1, 2, 3). Set this via the display on each inverter.

5️⃣ Step 5: Configuration in the Currentt Navigator​

After connecting the RS-485 cable and configuring the inverter, the device must be added in the Currentt Navigator.

  1. Click the settings icon (top right of the screen)
  2. Choose Setup Wizard
  3. Follow the on-screen steps

Manual configuration​

  1. Click the settings icon (top right of the screen)
  2. Go to Components
  3. Click the + button in the Inverters section
  4. Select Growatt
  5. Enter the connection details:
ParameterValue
ConnectionModbus RTU (RS-485)
Modbus address1 (default)
Baud rate9600
Data bits8
ParityNone (N / disabled)

🔗 Multiple inverters (daisy-chain)​

When using multiple Growatt inverters on the same RS-485 bus:

  1. Connect the inverters to each other via RS-485 (daisy-chain)
  2. Connect the first inverter to the Currentt Navigator
  3. Give each inverter a unique Modbus address (1, 2, 3, etc.)
  4. Place a 120Ω termination resistor at the end of the RS-485 bus (on the last inverter in the chain)

📋 Settings summary​

ParameterValue
ConnectionRS-485 (Modbus RTU)
ProtocolModbus RTU
Modbus address1 (default)
Baud rate9600
Data bits8
ParityNone (N / disabled)

🛟 Troubleshooting​

ProblemPossible causeSolution
No connectionA and B swappedCheck the polarity of the RS-485 connection
No connectionWrong Modbus addressCheck the Modbus address on the inverter display
No connectionWrong baud rateCheck that the baud rate matches (default 9600)
No connectionWrong protocolCheck that the protocol is set to Modbus RTU (not the Growatt proprietary protocol)
No connectionCable too long or damagedUse a shorter cable or check for damage
Unreliable communicationNo terminationPlace a 120Ω termination resistor at the end of the RS-485 bus
No communicationInverter in sleep modeThe inverter may not communicate when there is no PV production (depending on model and firmware)
Read-only, no controlExternal EMS not enabledEnable the External EMS mode via the inverter display