CeilSense Overview

The CeilSense is a professional-grade ceiling-mounted sensor that combines mmWave radar presence detection with environmental monitoring. Designed to fit standard downlight cutouts, it provides invisible room monitoring for CO₂, temperature, humidity, light, and pressure while detecting occupancy with up to 9m range.
🌟 Key Features
| Feature | Description |
|---|---|
| mmWave Radar | Hi-Link LD2412S — presence & motion detection, Ø 9m range, 75° FOV |
| CO₂ Monitoring | SCD41 sensor (400-5,000 ppm) — Complete version |
| Temperature | ±1.5°C accuracy (-10°C to +60°C) — Complete version |
| Humidity | 0-100% RH — Complete version |
| Barometric Pressure | BMP388 (300-1,100 hPa, ±0.08 hPa) |
| Light Intensity | BH1750 lux sensor (0-65,000 lux) |
| LED Ring | 16× WS2812B individually addressable RGB LEDs |
| Connectivity | WiFi or Ethernet (PoE) |
| Power Options | PoE (802.3af), 110-240 VAC, or USB-C |
| Ceiling Mount | 68mm hole diameter — fits standard Ø70mm downlight cutouts |
| Integration | ESPHome + Home Assistant |
📦 Product Variants
| Variant | Sensors Included |
|---|---|
| Basic | mmWave radar (presence & motion), light sensor, pressure sensor, LED ring |
| Complete | All Basic sensors + CO₂, temperature & humidity (SCD41) |
📚 Documentation
- Installation Guide — Mounting, power options, WiFi setup, Home Assistant
- Network Configuration — WiFi, Ethernet, PoE setup
- Usage Guide — Monitoring, automations, dashboard ideas
- Calibration — CO₂, temperature, radar calibration
- Sensor Definitions — All entities explained
- Troubleshooting — Common issues and solutions
- Technical Specifications — Detailed specs
- FAQ — Frequently asked questions
- Firmware — WiFi/Ethernet switching, OTA updates
- Warranty and Support — Warranty info and contact
🔌 Connectivity & Power Options
The CeilSense offers flexible installation options:
- WiFi: Ships as default, easy setup via captive portal
- Ethernet + PoE: Single cable for power & data — perfect for professional installations
- 110-240 VAC: Direct mains power via internal EU-designed circuit with galvanic isolation
- USB-C: 5V 1A for testing or alternative setups
👉 See the Network Configuration and Firmware Guide for setup instructions.
💡 LED Ring
The integrated 16-LED RGB ring provides:
- Status indication during boot and operation
- Custom lighting effects for ambiance
- Visual feedback for presence detection (debug mode)
⚠️ Note: Extended LED operation generates heat that can affect sensor readings. Use cooldown intervals or reduce brightness during intensive use.
🏠 100% Local Operation
The CeilSense works entirely locally with Home Assistant. No cloud account, no subscriptions, no data leaving your network. The only external communication is an optional firmware version check to GitHub.
💬 Need Help?
- Discord: smarthomeshop.io/discord — Community support with 7,500+ members
- Contact: smarthomeshop.io/contact — Direct support
- Quick Start: smarthomeshop.io/quick-start-ceilsense — Quick setup guide
- Product Site: ceilsense.nl/en — Product information