S1 Pro Multi Sense

The Sensy-One S1 Pro Multi Sense is an open-source presence and environmental sensor, built from the ground up with Home Assistant in mind. After extensive prototyping, firmware tuning, and valuable input from users and smart home enthusiasts, the S1 Pro brings together reliable presence detection, real-time air quality monitoring, and ambient light sensing — all in one compact, Home Assistant-ready device.

🔍 Seamless Home Assistant integration
The S1 Pro is automatically discovered in Home Assistant via BLE Improv when Bluetooth is available. If not, it starts a wireless access point for quick setup — no additional tools required.

⚡ Powered by ESP32-C3
At its core, the S1 Pro uses the ESP32-C3-MINI-1-N4 module — offering reliable Wi-Fi and Bluetooth Low Energy, low power consumption, and full support for ESPHome and Home Assistant integrations.

🔌 Flexible USB-C power configuration (add-on)
The S1 Pro includes a built-in, downward-facing USB-C port for standard mounting. For added flexibility, two optional modules connect via the rear Mezzanine connector: a male USB-C plug for direct connection to a wall adapter without cables, and a female USB-C port for placing the sensor upright, where bottom access isn't practical.

Please note: to use the sensor in a standing position, you’ll need the S1 Pro Female USB-C Add-on, which is not included as standard.

🏗️ Modular mounting options
The S1 Pro supports two optional mounting adapters for flexible placement: a ball mount for precise positioning in 90-degree corners, and a standard ball mount for clean, low-profile installation on any surface.

🏠 Precision-engineered enclosure
The custom case is optimized for minimal interference with mmWave signals and maximum airflow across the sensors — ensuring accurate environmental readings and efficient cooling to extend component lifespan. Printed on a Formlabs Form 4 resin printer, the enclosure features a smooth, professional finish with no visible layer lines, and measures just 50 mm high, 35 mm wide, and 25 mm deep.

🛰️ Advanced mmWave presence sensing
Powered by the Hi-Link LD2450 radar module, the S1 Pro tracks up to three targets simultaneously, including their position, speed, and movement in real time. It features a 120° field of view, 70° vertical coverage, and up to 6 meters range, with updates every 30 ms for smooth, accurate presence detection.

🎯 Customizable detection zones
Define up to 3 detection zones (expandable to 10 in a future update), plus 1 exclusion zone to ignore movement from devices like fans or 3D printers. Each zone includes adjustable presence delay and motion threshold settings, and reports zone-specific data such as target count, occupancy status, and movement activity.

💡 Full-color status LED
A bright WS2812B RGB LED on the back of the PCB projects light onto the wall, ideal for alerts, presence indication, or ambient effects.

🔔 Built-in buzzer
The integrated Huaneng MLT-8530 buzzer delivers clear audio alerts at 80–90 dB and 2.7 kHz, perfect for notifications, warnings, or presence feedback.

🌡️ Comprehensive environmental monitoring
Equipped with the advanced Bosch BME688 sensor, the S1 Pro delivers real-time insights into your indoor environment. It measures CO₂ equivalent, gas resistance, IAQ (Indoor Air Quality), VOC equivalent, humidity, temperature, and air pressure — giving you a complete picture of air quality and comfort in your space.

🔬 High-precision CO₂ sensing (add-on)
For highly accurate CO₂ measurements, the S1 Pro supports an optional Sensirion SCD40 module. This add-on also reports humidity and temperature, but its main strength is CO₂ accuracy. It connects directly to the main PCB via a Molex Mezzanine connector — no soldering required.

☀️ Ambient light and UV sensing
The integrated Lite-On LTR-390UV sensor measures both illuminance (Lux) and UV index (UVI), enabling smart lighting control and sun exposure awareness based on real-time ambient conditions.

🧠 Ready to geek out?
Dive into the specs on our GitHub, watch it in action on YouTube, or join the conversation on Discord. See you there!