Third Reality Smart Presence Sensor R2 Review: Easy Zigbee Setup, but Range and Consistency Divide Owners
The Third Reality Smart Presence Sensor R2 is a Zigbee 3.0 mmWave occupancy sensor that runs on three AA batteries and joins Home Assistant, SmartThings and Echo-based Zigbee setups easily. Owner experience is sharply split: the happy ones use it in a bathroom or a desk office and say it beats a motion sensor, while a larger group reports that it only detects people a metre or so away, flips between occupied and empty, or gets stuck on detected. Treat the rated range as a best case, and plan to place it close to where people sit, ideally with a return option in hand.
- Existing Zigbee households
- Small rooms such as bathrooms and offices
- Rooms with no nearby outlet
- Home Assistant users
Pros
- Easy Zigbee pairing with Home Assistant
- Good results reported in small rooms such as a bathroom or desk office
- Runs on three standard AA batteries, so no outlet or wiring is needed
- Five sensitivity levels plus environment learning
- Works with Alexa, SmartThings and Home Assistant through a Zigbee hub
Cons
- Many owners find reliable detection only within about a metre or three feet, far below the rated range
- Reports of flipping between occupied and empty, getting stuck on detected, or losing a seated person
- Requires a Zigbee hub or coordinator, with no Wi-Fi, Bluetooth, Thread or Z-Wave fallback
- Reports a single occupancy state, with no person count, light sensing or fall detection
- Battery powered, so it does not extend the Zigbee mesh as a router
- No Google Home, Apple Home or Matter support
Who is the Smart Presence Sensor R2 for?
It suits someone who already runs a Zigbee network and wants occupancy rather than simple motion in a small space. Owners who are pleased with it put it in a bathroom to keep the lights on while they are in the room, or on a desk in an office, and say it works better than the motion sensors it replaces. The battery body is compact and takes common AA cells, so it goes where no outlet exists, though one owner calls it bulky. A Zigbee hub or coordinator is required: Home Assistant through ZHA or Zigbee2MQTT, SmartThings, Aeotec, Homey, Hubitat or an Echo device with a built-in Zigbee hub.
What owners like about the R2
The praise is about setup and the concept. Pairing is described as easy and without hassle, and at least one owner who put a unit in a bathroom plans to swap several motion sensors for more of them. The 24 GHz radar is meant to keep a room marked as occupied while someone sits still, and the five sensitivity levels and environment learning are there to reduce false triggers. Presence and absence both work as automation triggers for lights and other devices.
What to know before you buy
The dominant complaint is detection range. The spec sheet rates it for 5 meters, yet several owners say it only registers someone standing within about a metre, or three feet, whatever sensitivity setting they choose, and that it misses people approaching from the side or walking straight toward it. Others report that it keeps toggling between occupied and empty in a quiet room, stays stuck on detected after everyone has left, or drops presence while someone is still sitting there so the lights switch off. Calibration helped clear a stuck state for one owner without fixing the overall behaviour. A thin object such as a photo frame in front of the sensor was enough for one owner to lose detection. One Home Assistant owner also reports that it stopped working after a core update, while the sensor itself seemed fine. It reports a single occupancy state with no person count, has no light sensor, is a battery end device that does not repeat Zigbee traffic, and has no Google Home, Apple Home or Matter path.
Is the Smart Presence Sensor R2 worth it?
It depends on the room. In a small bathroom or at a desk, where the sensor sits close to the person, owners get the behaviour they wanted. Across a living space or kitchen, a large share of owners find the working range far below the rating and the occupancy state unstable, and the low average rating reflects that. Buy it for close-range use only, test it in the exact spot before committing to a multi-sensor rollout, and consider a wired mmWave sensor if you need dependable coverage across a larger room.
Frequently asked questions
Does the Third Reality Smart Presence Sensor R2 need a hub?
Yes. It is a Zigbee 3.0 end device, so it needs a Zigbee hub or coordinator. Home Assistant (ZHA or Zigbee2MQTT), SmartThings, Aeotec, Homey, Hubitat and Echo devices with a built-in Zigbee hub all work.
How far can the Smart Presence Sensor R2 detect?
The rated maximum is 5 meters, about 16 feet, but several owners say detection is reliable only within roughly a metre or three feet, even after changing the sensitivity level. Test it in the exact spot where you plan to mount it.
Does the Smart Presence Sensor R2 work with Home Assistant?
Yes, through both ZHA and Zigbee2MQTT. Zigbee2MQTT documents it under model 3RPS01083Z and exposes battery level, occupancy, sensor calibration and sensor sensitivity. One owner reports it stopped working after a Home Assistant core update, so check the current integration notes before updating.
Does the Smart Presence Sensor R2 work with Apple Home or Google Home?
No. It is a plain Zigbee 3.0 accessory with no Matter profile, so neither platform can add it. The ecosystems it reaches through a Zigbee hub are Alexa, Samsung SmartThings and Home Assistant.
What batteries does the Smart Presence Sensor R2 use?
Three standard AA batteries, included in the box, rated for up to 3 years in typical usage. There is no USB or mains option, which is what lets it go where no outlet exists.
