Daly BMS Sensor

The daly_bms sensor platform allows you to use a Daly Smart BMS (more info) with ESPHome.

The BMS communicates via UART.

Component/Hub

# Example configuration entry
daly_bms:
  update_interval: 20s

Configuration variables

update_interval (Optional, Time): Delay between data requests.
address (Optional, int): Address to use, defaults to 0x80.

Sensor

A sensor platform to read BMS data

sensor:
  - platform: daly_bms
    voltage:
      name: "Battery Voltage"
    current:
      name: "Battery Current"
    battery_level:
      name: "Battery Level"
    max_cell_voltage:
      name: "Max Cell Voltage"
    max_cell_voltage_number:
      name: "Max Cell Voltage Number"
    min_cell_voltage:
      name: "Min Cell Voltage"
    min_cell_voltage_number:
      name: "Min Cell Voltage Number"
    max_temperature:
      name: "Max Temperature"
    max_temperature_probe_number:
      name: "Max Temperature Probe Number"
    min_temperature:
      name: "Min Temperature"
    min_temperature_probe_number:
      name: "Min Temperature Probe Number"
    remaining_capacity:
      name: "Remaining Capacity"
    cells_number:
      name: "Cells Number"
    temperature_1:
      name: "Temperature 1"
    temperature_2:
      name: "Temperature 2"
    cell_1_voltage:
      name: "Cell 1 Voltage"
    cell_2_voltage:
      name: "Cell 2 Voltage"
    cell_3_voltage:
      name: "Cell 3 Voltage"
    cell_4_voltage:
      name: "Cell 4 Voltage"

Configuration variables

voltage (Optional): Voltage of the battery pack connected to Daly BMS. All options from Sensor.
current (Optional): Current flowing through the BMS (input or output from battery). All options from Sensor.
battery_level (Optional): Battery level in % (SoC). All options from Sensor.
max_cell_voltage (Optional): The cell of the battery with the higher voltage. All options from Sensor.
max_cell_voltage_number (Optional): The cell number of the battery with the higher voltage. All options from Sensor.
min_cell_voltage (Optional): The cell of the battery with the lower voltage. All options from Sensor.
min_cell_voltage_number (Optional): The cell number of the battery with the lower voltage. All options from Sensor.
max_temperature (Optional): The higher temperature measured from the temperature sensors. All options from Sensor.
max_temperature_probe_number (Optional): The sensor number which has measured the higher temperature. All options from Sensor.
min_temperature (Optional): The lower temperature measured from the temperature sensors. All options from Sensor.
min_temperature_probe_number (Optional): The sensor number which has measured the lower temperature. All options from Sensor.
remaining_capacity (Optional): The capacity in Ah left in the battery. All options from Sensor.
cells_number (Optional): The number of cells in series in the battery pack. All options from Sensor.
temperature_1 (Optional): The first temperature sensor. All options from Sensor.
temperature_2 (Optional): The second temperature sensor. All options from Sensor.
cell_1_voltage (Optional): The voltage of cell number 1. Cell number can be from 1 to 16. All options from Sensor.

Text Sensor

Text sensor that indicates the status of BMS.

text_sensor:
  - platform: daly_bms
    status:
      name: "BMS Status"

Configuration variables

status (Optional): The BMS Status (Charging, Discharging, Stationary). All options from Text Sensor.

Binary Sensor

Binary sensor that indicates the status of MOS.

binary_sensor:
  - platform: daly_bms
    charging_mos_enabled:
      name: "Charging MOS"
    discharging_mos_enabled:
      name: "Discharging MOS"

Configuration variables

charging_mos_enabled (Optional): The BMS charging MOS status to enable the recharge of the battery. All options from Binary Sensor.
discharging_mos_enabled (Optional): The BMS discharging mos status to enable the load. All options from Binary Sensor.

Control BMS

At this moment Daly sensor platform doesn’t support controlling your BMS, but you can make some stuff using uart.write

First you need to setup binary sensors for charging and discharging MOS

binary_sensor:
  - platform: daly_bms
    charging_mos_enabled:
      name: "Daly Charging MOS"
      id: bin_daly_chg_mos # binary MOS sensor must have ID to use with switch
      internal: True # but you can make it internal to avoid duplication
    discharging_mos_enabled:
      name: "Daly Discharging MOS"
      id: bin_daly_dischg_mos # binary MOS sensor must have ID to use with switch
      internal: True # but you can make it internal to avoid duplication

Then you can add switches

switch:
  - platform: template
    name: "Daly Charging MOS"
    lambda: |-
      if (id(bin_daly_chg_mos).state) {
        return true;
      } else {
        return false;
      }
    turn_on_action:
      - uart.write:
          data: [0xA5, 0x40, 0xDA, 0x08, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xC8]
      - logger.log:
          format: "Send cmd to Daly: Set charge MOS on"
    turn_off_action:
      - uart.write:
          data: [0xA5, 0x40, 0xDA, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xC7]
      - logger.log:
          format: "Send cmd to Daly: Set charge MOS off"

  - platform: template
    name: "Daly Discharging MOS"
    lambda: |-
      if (id(bin_daly_dischg_mos).state) {
        return true;
      } else {
        return false;
      }
    turn_on_action:
      - uart.write:
          data: [0xA5, 0x40, 0xD9, 0x08, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xC7]
      - logger.log:
          format: "Send cmd to Daly: Set discharge MOS on"
    turn_off_action:
      - uart.write:
          data: [0xA5, 0x40, 0xD9, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xC6]
      - logger.log:
          format: "Send cmd to Daly: Set discharge MOS off"

Also you can add select to change battery level

select:
  - platform: template
    name: "Daly Battery Level setup"
    optimistic: True
    options:
      - 100%
      - 75%
      - 50%
      - 25%
      - 0%
    initial_option: 100%
    set_action:
      then:
        - if:
            condition:
              lambda: 'return x == "100%";'
            then:
              - uart.write:
                  data: [0xA5, 0x40, 0x21, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xE8, 0xF9]
              - logger.log:
                  format: "Send cmd to Daly: Set SOC to 100%"
            else:
              - if:
                  condition:
                    lambda: 'return x == "75%";'
                  then:
                    - uart.write:
                        data: [0xA5, 0x40, 0x21, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xEE, 0xFE]
                    - logger.log:
                        format: "Send cmd to Daly: Set SOC to 75%"
                  else:
                    - if:
                        condition:
                          lambda: 'return x == "50%";'
                        then:
                          - uart.write:
                              data: [0xA5, 0x40, 0x21, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xF4, 0x03]
                          - logger.log:
                              format: "Send cmd to Daly: Set SOC to 50%"
                        else:
                          - if:
                              condition:
                                lambda: 'return x == "25%";'
                              then:
                                - uart.write:
                                    data: [0xA5, 0x40, 0x21, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFA, 0x08]
                                - logger.log:
                                    format: "Send cmd to Daly: Set SOC to 25%"
                              else:
                                - if:
                                    condition:
                                      lambda: 'return x == "0%";'
                                    then:
                                      - uart.write:
                                          data: [0xA5, 0x40, 0x21, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0E]
                                      - logger.log:
                                          format: "Send cmd to Daly: Set SOC to 0%"

UART Connection

Connect RX from BMS to TX in ESP board and TX from BMS to RX in ESP board

3.3v Warning: some BMS 3.3v cant source large currents and may not work to properly power the ESP. If you are having WIFI connection issues or similar, try a different power source. There is 12-15v available on the Daly connector which via a proper step-down converter can properly power the ESP.

On the ESP32 (untested on ESP8266) if you are having missing data (such as Temperature 1/2), it may be due to UART buffer size. Add the following to your configuration to increase the buffer from the default 256 to 512.

uart:
  ...
  rx_buffer_size: 512

Daly BMS Sensor

Component/Hub

Configuration variables

Sensor

Configuration variables

Text Sensor

Configuration variables

Binary Sensor

Configuration variables

Control BMS

UART Connection

See Also