Connecting Multiple Modbus Sensors to A16 (ESPHome)

[Gleb]

I'd like to greet all the forum members. I’m reaching out to ask for your help with an issue I’m experiencing.

I connected 7 sensors to an RS485 Modbus bus, but only 4 of them work simultaneously. When I connect each sensor individually, they all respond correctly. However, when I try to initialize more than 4 sensors in the YAML configuration (e.g., 1-2-3-4), they are displayed and work fine. But as soon as I add more sensors (e.g., 5-6-7), some of them stop responding or are not displayed at all.
I am using an A16 with ESPHome integrated into Home Assistant.


...
uart:
  - id: uart_modbus
    tx_pin: GPIO13
    rx_pin: GPIO16
    baud_rate: 4800
modbus:
  - uart_id: uart_modbus
    setup_priority: -10
    send_wait_time: 500 ms
    id: modbus1
modbus_controller:
  - id: modbus_sensor_2
    address: 0x02  
    modbus_id: modbus1
    update_interval: 5s
    offline_skip_updates: 2
    max_cmd_retries: 4
 
  - id: modbus_sensor_4
    address: 0x04  
    modbus_id: modbus1
    update_interval: 5s
    offline_skip_updates: 2
    max_cmd_retries: 4
  - id: modbus_sensor_7
    address: 0x07  
    modbus_id: modbus1
    update_interval: 5s
    offline_skip_updates: 2
    max_cmd_retries: 4
  - id: modbus_sensor_8
    address: 0x08  
    modbus_id: modbus1
    update_interval: 5s
    offline_skip_updates: 2
    max_cmd_retries: 4
...
...
sensor:
  - platform: modbus_controller
    modbus_controller_id: modbus_sensor_2
    name: "t_2"
    id: temperature_sensor_2
    address: 0x0001
    register_type: holding
    value_type: U_WORD
    force_new_range: true
    unit_of_measurement: "°C"
    accuracy_decimals: 2
    filters:
      - multiply: 0.1
  - platform: modbus_controller
    modbus_controller_id: modbus_sensor_2
    name: "h_2"
    id: humidity_sensor_2
    address: 0x0000
    register_type: holding
    value_type: U_WORD
    unit_of_measurement: "%"
    accuracy_decimals: 2
    filters:
      - multiply: 0.1
  - platform: modbus_controller
    modbus_controller_id: modbus_sensor_4
    name: "t_4"
    id: temperature_sensor_4
    address: 0x0001
    register_type: holding
    value_type: U_WORD
    force_new_range: true
    unit_of_measurement: "°C"
    accuracy_decimals: 2
    filters:
      - multiply: 0.1
  - platform: modbus_controller
    modbus_controller_id: modbus_sensor_4
    name: "h_4"
    id: humidity_sensor_4
    address: 0x0000
    register_type: holding
    value_type: U_WORD
    unit_of_measurement: "%"
    accuracy_decimals: 2
    filters:
      - multiply: 0.1
   
  - platform: modbus_controller
    modbus_controller_id: modbus_sensor_7
    name: "t_i"
    id: temperature_sensor_7
    address: 0x0001
    register_type: holding
    value_type: U_WORD
    force_new_range: true
    unit_of_measurement: "°C"
    accuracy_decimals: 2
    filters:
      - lambda: |-
          if (x > 32767) {
          return (x - 65536) / 10.0;
          } else {
          return x / 10.0;
          }
   
  - platform: modbus_controller
    modbus_controller_id: modbus_sensor_8
    name: "t_k"
    id: temperature_sensor_8
    address: 0x0001
    register_type: holding
    value_type: U_WORD
    force_new_range: true
    unit_of_measurement: "°C"
    accuracy_decimals: 2
    filters:
      - multiply: 0.1  
...