esphome-junctek_kgf

Component for esphome to read status from a Junctek KG-F coulometer/battery monitor via UART

Features

Connects to the Junctek KGF series battery monitor via UART (RS-485 adapter needed) and retrieves the following values:

• Battery Voltage
• Battery Percent
• Current Amps
• Temperature
• ...

Requirements

• ESPHome

Tested setup

Tested on ESP32 using a RS-485 uart into a Junctek KG110F, but should work on an ESP8266 and any of the KG-F series

Usage

Connect hardware.

The ESP32 needs to be connected via an RS-485 module (https://www.aliexpress.com/item/1005001621746811.html) to the RS-485 on the monitor using a 4p4c (RJ9/RJ10) connector. The ESP32 should be on the same ground as Junctek, or the RS-485 module should be opto-isolated (https://www.aliexpress.com/w/wholesale-ttl-to-rs485-isolated.html).

ESPHOME Config

The applicable config for the device should look something like:

external_components:
  - source: github://tfyoung/esphome-junctek_kgf

uart:
#  connected to Tx on RS-485 module
  tx_pin: 26
  rx_pin: 27
  baud_rate: 115200

sensor:
  - platform: junctek_kgf
    address: 1
    invert_current: true
    voltage:
      name: "Battery Voltage"
    current:
      name: "Battery Current"
    power:
      name: "Power"
    battery_level:
      name: "Battery Level"
    amp_hour_remain:
      name: "Ah Remaining"
    temperature:
      name: "Ambient Temperature"
    battery_ohm:
      name: "Battery Resistance"
    relay_status:
      name: "Relay Status"
    battery_charged_energy:
      name: "kWh Charged Total"
    battery_discharged_energy:
      name: "kWh Discharged Total"

Not all sensors need to be added. Address is assumed to be 1 if not provided. (this is configured on the monitor) invert_current: This inverts the reported current, it's recommended to include this option with either true or false (which ever makes the current make more sense for your setup). The default is currently false (and false will match previous behaviour), but may change to true in future updates.

Future work

More sensors/statistics are possible, as is adjusting various configuration, but haven't currently been added. File an issue if there anything you want to see.