ESP PowerMeter

Energy logging und current/voltage meter. Solar panel tester and a Home Assistant MQTT battery sensor

Web Interface:

Features

• 3 Modes: Coulometer / Solar Tester / Power Meter
• 3 Battery Types Supported: Li-ion, LiPo, LiFePO4
• Fully configurable with OLED UI
• Wi-Fi Support: Access Point mode or join an existing network
• Additional Web Interface
• MQTT Support: can be used as a sensor with Home Assistant
• Max Voltage: 36V (listed 5V BEC supports max. 30V)

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Parts needed

• ESP32-C3 PRO MINI
• 5V BEC (iFlight 5V 2-8S)
• INA226 Module + 3920 5W 2mΩ Shunt (R002)
  or custom INA226 PCB (see Hardware directory)
• *male/female XT60 connectors
• 1.5" 128x128 I2C OLED Display (optional)
• 2x Tactile Buttons (optional)
• Real Time Clock RTC DS3231 module (optional)
• 3D Printed Case (see STLs directory)

RTC and NON-RTC Versions

The main difference to the non-RTC version ist that the RTC version of the code uses an DS3231 real time clock for measurement and displays graph labels with the correct time in the Web-UI.

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Device Image:

Button Mapping

MQTT Entities in Home Assistant

Custom INA266 Sensor PCB with optional DS3231:

Connection Diagram

To be determined (TBD)

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