The Elektor ESP32 Energy Meter is a device designed for real-time energy monitoring and smart home integration. Powered by the ESP32-S3 microcontroller, it offers robust performance with modular and scalable features.
The device uses a 220 V-to-12 V step-down transformer for voltage sampling, ensuring galvanic isolation and safety. Its compact PCB layout includes screw-type terminal blocks for secure connections, a Qwiic connector for additional sensors, and a programming header for direct ESP32-S3 configuration. The energy meter is compatible with single-phase and three-phase systems, making it adaptable for various applications.
The energy meter is simple to set up and integrates with Home Assistant, offering real-time monitoring, historical analytics, and automation capabilities. It provides accurate measurements of voltage, current, and power, making it a valuable tool for energy management in homes and businesses.
Features
Comprehensive Energy Monitoring: Get detailed insights into your energy usage for smarter management and cost savings.
Customizable Software: Tailor functionality to your needs by programming and integrating custom sensors.
Smart Home Ready: Compatible with ESPHome, Home Assistant, and MQTT for full Smart Home integration.
Safe & Flexible Design: Operates with a 220 V-to-12 V step-down transformer and features a pre-assembled SMD board.
Quick Start: Includes one Current Transformer (CT) sensor and access to free setup resources.
Specifications
Microcontroller
ESP32-S3-WROOM-1-N8R2
Energy Metering IC
ATM90E32AS
Status Indicators
4x LEDs for power consumption indication2x Programmable LEDs for custom status notifications
User Input
2x Push buttons for user control
Display Output
I²C OLED display for real-time power consumption visualization
Input Voltage
110/220 V AC (via step-down transformer)
Input Power
12 V (via step-down transformer or DC input)
Clamp Current Sensor
YHDC SCT013-000 (100 A/50 mA) included
Smart Home Integration
ESPHome, Home Assistant, and MQTT for seamless connectivity
Connectivity
Header for programming, Qwiic for sensor expansion
Applications
Supports single-phase and three-phase energy monitoring systems
Dimensions
79.5 x 79.5 mm
Included
1x Partly assembled board (SMDs are pre-mounted)
2x Screw terminal block connerctors (not mounted)
1x YHDC SCT013-000 current transformer
Required
Power transformer not included
Downloads
Datasheet (ESP32-S3-WROOM-1)
Datasheet (ATM90E32AS)
Datasheet (SCT013-000)
Frequently Asked Questions (FAQ)
From Prototype to Finished Product
What started as an innovative project to create a reliable and user-friendly energy meter using the ESP32-S3 microcontroller has evolved into a robust product. Initially developed as an open-source project, the ESP32 Energy Meter aimed to provide precise energy monitoring, smart home integration and more. Through meticulous hardware and firmware development, the energy meter now stands as a compact, versatile solution for energy management.
The SparkFun Weather Shield uses the Si7021 humidity / temperature sensor, the MPL3115A2 barometric pressure sensor, and the ALS-PT19 light sensor. The shield utilizes the MPL3115A2 and Si7021 Arduino libraries.
The SparkFun Weather Shield comes with two unpopulated RJ11 connector spaces and a 6-pin GPS connector. Finally, each Weather Shield can operate from 3.3 V up to 16 V and has built-in voltage regulators and signal translators.
Check out the GitHub page, Schematics, and Eagle Files for more information.
This portable WiFi weather station is the perfect blend of functionality and style, offering real-time updates on temperature, humidity, and time – all at a single glance.
Featuring a clear digital display, the station ensures that weather and time data are always easy to read and understand. Its minimalist design integrates seamlessly into any environment, adding a touch of modern sophistication without drawing unnecessary attention.
Features
Multi-Function Display: Shows weather, atmospheric pressure, min/max temperature, wind speed, city, country/region, date, day of the week, outdoor temperature & humidity – all at a glance.
Custom GIF Animations: Upload your own GIFs for a personalized display experience.
WiFi Connectivity: Automatically connects to the Internet to retrieve real-time weather and time data.
Power Supply: USB-C
Durable Plastic Casing
Dimensions: 45 x 35 x 40 mm
A meteorologically minded Raspberry Pi HAT designed to make hooking up weather sensors a breeze (or a squall, or a gale). Weather HAT is an all-in-one solution for hooking up climate and environmental sensors to a Raspberry Pi. It has a bright 1.54' LCD screen and four buttons for inputs. The onboard sensors can measure temperature, humidity, pressure and light. The sturdy RJ11 connectors will let you easily attach wind and rain sensors. It will work with any Raspberry Pi with a 40-pin header. You could install it outside in a suitable weatherproof enclosure and connect to it wirelessly – logging the data locally or piping it into Weather Underground, a MQTT broker or a cloud service like Adafruit IO. Alternatively, you could house your weather Pi inside and run wires to your weather sensors outside - making use of the nice screen to display readouts. Features 1.54' IPS LCD screen (240 x 240) Four user-controllable switches BME280 temperature, pressure, humidity sensor (datasheet) LTR-559 light and proximity sensor (datasheet)
Nuvoton MS51 microcontroller with inbuilt 12-bit ADC (datasheet) RJ11 connectors for connecting wind and rain sensors (optional) HAT-format board Fully-assembled Compatible with all 40-pin header Raspberry Pi models Downloads Python library Schematic Included Weather HAT 2 x 10 mm standoffs
Elektor GREEN and GOLD members can download their digital edition here.
Not a member yet? Click here.
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Elektor GREEN and GOLD members can download their digital edition here.
Not a member yet? Click here.
Small Thermal Imaging CameraAn Arduino UNO-Based DIY Solution
Project Update #3: ESP32-Based Energy MeterIntegration and Testing with Home Assistant
2024: An AI OdysseyEnhancing Object Detection: Integrating Refined Techniques
Raspberry Pi Goes AINew Kit Incorporates M.2 HAT+ With AI Accelerator
Weather Station SensorsWhich One Should You Choose?
AI-Based Water Meter Reading (1)Get Your Old Meter Onto the IoT!
A GSM AlarmHarnessing GSM Technology for Remote Garage Safety
Low-Power Thread Devices Optimized and ScrutinizedLow Power … Low Effort?
From Life’s ExperienceThe Gender Gap
DIY Cloud ChamberMaking Invisible Radiation Visible
SparkFun Thing Plus MatterA Versatile Matter-Based IoT Development Board
IoT RetrofittingMaking RS-232 Devices Fit for Industry 4.0
Enabling IoT with 8-Bit MCUs
Technology Drives SustainabilityAdvances Lead to More Efficient Use of Energy in Many Applications
AWS for Arduino and Co. (1)Using AWS IoT ExpressLink in Real Life
Airflow Detector Using Arduino OnlyNo External Sensors Needed!
Water Leak DetectorConnected to Arduino Cloud
CrystalsPeculiar Parts, the Series
Universal Garden LoggerA Step Towards AI Gardening
Analog 1 kHz GeneratorSine Waves with Low Distortion
Miletus: Using Web Apps OfflineSystem and Device Access Included!
From 4G to 5GIs It Such an Easy Step?
Starting Out in Electronics……Balances Out
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