ESPHome to KNX via Home Assistant: Sensors and Switch States
Bridge ESPHome devices to KNX through Home Assistant: expose ESP32 sensor values and switch states, accept KNX commands, map DPTs correctly and avoid feedback loops.
ESP32 Power Failure Detector for Home Assistant & ESPHome
Quick Summary (TL;DR):A reliable ESP32 power failure detector for Home Assistant needs two independent paths: the ESP32 stays alive from a UPS or battery-backed 5 V supply, while a separate isolated signal tells it whether the monitored mains circuit is…
BH1750 Lux Sensor with Home Assistant: ESP32 Lighting Automation
Quick Summary (TL;DR):The BH1750 is one of the easiest ways to give an ESP32 a real lux measurement for Home Assistant. Unlike an LDR/photoresistor, it returns calibrated digital illuminance over I²C, so Home Assistant sees an actual value in lux…
ESP32 Indoor Air Quality Station: SCD41 + SGP40 + PMS5003 + SHT45
Quick Summary (TL;DR):A serious Home Assistant indoor-air-quality station should not try to turn one cheap “air quality” sensor into everything. Use SCD41 for true CO₂, SGP40 for VOC Index, PMS5003 for PM1, and SHT45 for the primary room temperature and…
PMS5003 ESPHome Troubleshooting: UART, Sleep Mode & Bad PM Readings
Quick Summary (TL;DR):Most PMS5003 + ESPHome problems come from five areas: UART wiring, wrong sensor type, unstable power or airflow, misunderstanding active/passive mode, or mistaking real particulate spikes for bad data. The normal PMS5003 uses 9600 baud. For continuous monitoring,…
Best ESP32 for Bluetooth Proxy: C3 vs C6 vs S3 vs ESP32
Quick Summary (TL;DR):For a dedicated Home Assistant Bluetooth Proxy in 2026, the ESP32-C3 is the best-value Wi-Fi proxy: it is cheap, tiny, widely available, has Bluetooth 5 LE, 400 KB SRAM and more than enough CPU for continuous BLE scanning…
ESP32 Roller Shutter / Blind Control with Home Assistant & ESPHome
Quick Summary (TL;DR):A conventional roller shutter or tubular blind motor normally uses two direction inputs: OPEN/UP and CLOSE An ESP32 can control those directions through two relay outputs and expose the motor as a native Home Assistant cover entity with…
ESP32 Water Tank Level Monitor with Home Assistant & ESPHome
Quick Summary (TL;DR):You can turn an ESP32 into a reliable water tank level monitor for Home Assistant using an ultrasonic distance sensor such as the JSN-SR04T/AJ-SR04M or, for difficult tanks, a hydrostatic pressure sensor. The ESP32 does not measure “water…
ESP32 Fan RPM / Tachometer with Home Assistant & ESPHome
Quick Summary (TL;DR):You can monitor the real speed of a 3-wire or 4-wire DC fan with an ESP32 and ESPHome by reading the fan’s tachometer / RPM output. On standard PC-style fans, the tach wire is typically an open-collector output:…
ESP32 mmWave + PIR Presence Fusion for Home Assistant & ESPHome
Quick Summary (TL;DR):Combining a PIR motion sensor with a mmWave presence sensor such as the LD2410 gives Home Assistant a much better occupancy signal than either sensor alone. The PIR is excellent at detecting a person entering because it reacts…