Introduction: MODBUS-TCP ESPHOME/mqtt Gateway
Simple ModbusTCP to Esphome/Mqtt gateway
Supplies
ESP32 board
EBYTE NT1
https://www.aliexpress.com/item/1005003882507376.html
EBYTE V5.3 config tool
Step 1: Starting NT1
First, connect the EBYTE NT1 to the router with a LAN cable and give it 3.3v power
Then run the EBYTE config tool to search for the device
Attachments
Step 2: Config NT1 for Modbus TCP to Serial
What needs to be changed in the tool...
Network parameters:
Network mode :TCP client
Remote IP -> your modbusTCP device adress
Remote port -> your modbusTCP device port
Modbus parameters:
Modbus gateway : Simple
ModbusTCP to RTU : Enable
Step 3: TESTING
To test the connection, I recommend first trying the USB-serial connection and the ModbusPoll program. Then you can see at which addresses the data is located
https://www.modbustools.com/modbus_poll.html
Step 4: ESPHOME Config
Wiring:
NT1 RX to esp32 pin18
NT1 TX to esp32 pin19
First of all, you have to check in the manual of your ModbusTCP device where the data is located either "holding" or "read" registers. And with the ModbusPoll software, you can find out the data address .
ESPHOME CODE:
captive_portal:
uart:
- id: uart_1
tx_pin: GPIO18
rx_pin: GPIO19
baud_rate: 115200
modbus:
id: modbus1
modbus_controller:
- id: modbus_device
address: 0x1 ## address of the Modbus slave device on the bus
modbus_id: modbus1
setup_priority: -10
sensor:
- platform: modbus_controller
name: "Oxyquard_1_O2"
address: 2
register_type: "holding"
value_type: FP32
accuracy_decimals: 2
unit_of_measurement: "mg/L"
filters:
- filter_out: 0
- platform: modbus_controller
name: "Oxyquard_1_o2_temp"
address: 8
register_type: "holding"
value_type: FP32
accuracy_decimals: 1
unit_of_measurement: "C"
- platform: modbus_controller
name: "Oxyquard_1_CO2"
address: 12
register_type: "holding"
value_type: FP32
accuracy_decimals: 2
unit_of_measurement: "mg/L"
