From 53,72€
65,00€ incl. 21% VAT
Recessed ceiling sensor that combines advanced occupancy detection, ambient light monitoring, and an optional sensor for real-time temperature, humidity, and CO₂. Standard features:
Optional extra: USB-C Adapter Set.
The CeilSense can be powered via PoE (if you have a suitable PoE network connection) or USB-C. PoE is not required; USB-C always provides an alternative power source. Of course, the 110–240 V input remains available.
You can switch between Wi-Fi and Ethernet firmware at any time without making any hardware changes. The connection method selection is entirely software-driven, allowing you to customize the setup to your specific situation.
Need more info? View the full product page or jump straight to the documentation.
Ø 68 × 45 mm - fits perfectly in standard GU10 spot holes
- Wi-Fi IEEE 802.11 b/g/n (2.4 GHz), supports WPA/WPA2 security
- Ethernet (RJ45) with Power over Ethernet (PoE) support for stable network connection
Standard: HLK-LD2412 mmWave radar for accurate presence detection (±75° coverage, 9m range)
Optional: LD2450 mmWave sensor for advanced position tracking and multiple person detection
Future variants: In development for extended functionalities
- SCD41 module for CO₂ measurement (400-40,000 ppm)
- Temperature measurement (-10°C to +60°C, ±0.5°C accuracy)
- Humidity (0-100% RH, ±6% accuracy)
- BH1750 light sensor (0-65,535 lux)
16 individually addressable WS2812 RGB LEDs for ambient lighting, status indication, circadian lighting and subtle night light. Note: Prolonged LED use may affect temperature measurements due to heat generation.
- 110-240 VAC mains voltage via high-quality, CE-certified power supply with galvanic isolation
- USB-C port for power supply (5V, minimum 1A)
- Power over Ethernet (PoE) for combined power and data
- Requires a 68mm diameter hole and minimum 45mm installation depth in ceiling or wall
- Fits perfectly in existing GU10, MR16 or other spot holes
- Easy mounting with spring clips that automatically expand
- Suitable for both round and square junction boxes
- Ideal mounting height: ceiling or wall at 1-1.5m height
IP20 (suitable for indoor use)
Fully integrated with Home Assistant via ESPHome firmware, including support for OTA (Over The Air) firmware updates
- HLK-LD2412: 9 meter range with ±75° detection angle, detects even small movements like breathing
- LD2450 (optional): 9 meter range with ±75° detection angle, with advanced position tracking
European designed and manufactured • CE certified for safety and quality
Modular design for future-proofing with planned support for additional sensors and functionalities
Find answers to the most frequently asked questions about CeilSense variants and installation.
The CeilSense is an all-in-one built-in ceiling sensor that fits in a standard 68mm spot hole. It detects presence via advanced mmWave radar, measures environmental parameters and has 16 RGB LEDs for ambient lighting. Perfect for invisible integration into your ceiling.
CeilSense is built as a modular platform. The base variant focuses on reliable mmWave presence detection, lux sensing and RGB feedback. Variants with additional climate sensors add CO2, temperature and humidity data for more advanced automations.
The CeilSense works 100% locally! No cloud connection is required and all your data stays within your own network. This guarantees maximum privacy and fast response times. The sensor communicates directly with your Home Assistant installation.
Yes! The CeilSense runs on ESPHome, a fully open-source platform. You have complete access to the configuration and can customize it to your needs. The source code and documentation are available on our GitHub repository.
Yes, the CeilSense requires Home Assistant. The product is specifically designed for Home Assistant and does not work standalone. You need a working Home Assistant installation to use and configure the sensor.
The mmWave (millimeter wave) radar emits radio waves that reflect off objects and people. The CeilSense uses the HLK-LD2412 sensor that can detect even minimal movements like breathing, making it ideal for presence detection. Unlike PIR sensors, it also detects stationary people.
The standard HLK-LD2412 sensor has a range of up to 5 meters, ideal for smaller spaces. You can optionally upgrade to the LD2410 sensor with a range of up to 8 meters for larger rooms. The ceiling installation provides an optimal overview of the space.
The 16 WS2812 RGB LEDs offer endless possibilities! Use them as a night light, status indicator (e.g., red = high CO2), ambient lighting or visual notifications. Through Home Assistant you can control each LED individually or create beautiful effects.
The CeilSense Complete uses the SCD41 sensor from Sensirion, a Swiss manufacturer known for their high-quality sensors. The accuracy is ±50 ppm at 400-2000 ppm. The sensor auto-calibrates and also measures temperature and humidity.
The BH1750 lux sensor measures the ambient light in the room. With this you can create automations like: only turn on the light when there's motion if it's dark, or adjust the brightness of the RGB LEDs based on ambient light.
The CeilSense is designed for the standard 68mm spot hole used in most European ceilings. You can replace an existing spot or drill a new hole. The sensor fits in ceilings with at least 50mm space above.
The CeilSense offers three power options: 1) AC 100-240V directly to mains power (ideal when replacing a spot), 2) USB-C 5V for flexible placement, 3) PoE (Power over Ethernet) with optional adapter for combined power and network via one cable.
The CeilSense connects via Wi-Fi. On first startup, the sensor creates its own Wi-Fi network that you connect to. Through a simple web interface you enter your Wi-Fi credentials, and the sensor is automatically discovered in Home Assistant.
With USB-C power, installation is plug-and-play. For AC connection we recommend having this done by an electrician due to working with mains voltage. Software configuration is simple - the sensor is automatically discovered in Home Assistant.
Firmware updates are installed over-the-air (OTA). You'll receive a notification in Home Assistant when an update is available. With one click, the new firmware is downloaded and installed without physically touching the sensor.
The CeilSense is a built-in solution for the ceiling with RGB LEDs, while the UltimateSensor is a freestanding sensor with more sensors (PM, sound) and optional voice assistant. Choose CeilSense for invisible integration, UltimateSensor for maximum functionality.
Choose the base variant if you mainly need presence detection and lighting automations, for example in a hallway, toilet or utility room where air-quality monitoring is less relevant. It is usually the most efficient option for multiple rooms.
Choose a variant with climate sensors for living rooms and bedrooms where air quality matters. CO2, temperature and humidity data improve ventilation and climate automations and help maintain a healthier indoor environment.
PIR sensors only detect motion - as soon as you sit still they become blind. mmWave radar also detects breathing and small movements, so it keeps seeing you even when watching TV or sleeping. No more false 'lights off' while you're still there!
All CeilSense products come with a 2-year warranty. Should anything go wrong within this period, we'll replace the product free of charge. We stand behind the quality of our products.
We offer support through multiple channels: comprehensive documentation on our website, an active Discord community where you can ask questions, and direct email support. Most questions are answered within 24 hours.
You have 14 days to reconsider after receiving your order. Not satisfied? Return the product in original condition and we'll refund the full purchase amount. Contact our customer service to start a return.
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