What is a motion sensor?
A PIR sensor that detects movement and triggers lighting, security, or automations.
The essentials
- Detects movement via heat change (PIR)
- Great for corridors, entrances, and stairs
- Battery-powered options via Zigbee, Thread, Matter
- Pairs with cameras for verified alerts
Direct answer
A motion sensor is typically a passive infrared (PIR) device that detects the change in heat when a person moves across its field of view. It reports on/off events to a controller, which can switch lights, arm cameras, or trigger scenes. Motion sensors are cheap, low-power, and reliable for corridors, entrances, and other transit spaces in UAE villas and apartments.
Detailed explanation
A PIR sensor sees only changes in infrared radiation, so a stationary person can be missed after the initial trigger. This is fine for a hallway — light comes on when you walk in, holds for a timeout, and switches off — but poor for a study or cinema room, where a presence sensor is the right tool.
In UAE homes motion sensors are also the cheapest way to add security context — a hallway triggering after midnight, a garage triggering during a trip, or an entrance triggering while Away.
Decision guide
Choose motion (PIR)
corridors, stairs, garages
Choose presence (mmWave)
seated or stationary rooms
Combine with contact sensors
verified security alerts
Common mistakes and best practices
What to avoid, what to do
- Mount 2.2–2.5 m high, angled across the walkway
- Match timeouts to the room use, not one global value
- Use battery sensors sparingly — plan for battery service
- Mounting a PIR facing direct sunlight or an AC vent
- Using PIR alone in cinema, study, or meeting rooms
- Setting a 5-second timeout, causing constant retriggering
Frequently asked questions
Frequently asked questions
Do motion sensors work in the dark?
Yes — PIR sees infrared heat, not visible light.
How long do batteries last?
Typically 1–3 years depending on traffic and reporting interval.
Can they trigger cameras?
Yes — a controller can arm or record a camera when motion fires.
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