Ceiling motion presence detector Legrand 999835 IP20 84×36 mm

Ceiling motion presence detector Legrand 999835 IP20 84×36 mm is a ceiling-mounted sensor for indoor use that detects both motion and presence to control lighting and automation systems. With IP20 protection and a compact 84×36 mm format, the device is designed for flush or recessed ceiling installations in offices, corridors, restrooms and similar interior spaces where automatic switching and occupancy detection are required.

Advantages

The detector combines motion and presence sensing to provide reliable activation of lighting and systems while reducing unnecessary energy consumption. Its compact dimensions make it suitable for discreet ceiling installation, and the IP20 rating indicates suitability for dry indoor environments. The sensor integrates with standard lighting control circuits and delivers stable detection performance across typical indoor layouts.

Suitable for

• Office rooms and open-plan workspaces
• Corridors, stairwells and passageways
• Restrooms and washrooms
• Storage rooms and small utility areas
• Lighting automation in residential and commercial interiors

Key specifications

• Mounting: ceiling (flush or recessed installation)
• Protection class: IP20 — suitable for indoor, dry environments
• Dimensions: 84 × 36 mm (diameter/height format for ceiling fitting)
• Detection type: motion and presence detection
• Integration: designed for connection to lighting and automation control circuits
• Typical applications: occupancy sensing for automatic switching and energy saving

How to use

Install the detector into a compatible ceiling cut-out following mounting instructions and electrical safety standards. Connect the sensor to the lighting circuit or building automation wiring according to wiring diagrams provided by the system integrator or product manual. Adjust detection sensitivity and time-delay settings if available to match room size and use patterns. Test the device after installation to confirm reliable detection coverage and switching behaviour before regular operation.

Usage recommendations

Mount the detector centrally in the room or along the main circulation path for optimal coverage; avoid pointing the sensor directly at large windows or air-conditioning outlets that may cause false triggers. Use sensitivity and time-delay adjustments to minimize unwanted switching while ensuring prompt response when spaces become occupied. For humid or outdoor locations select a product with a higher protection rating.