SONOFF SenseGuard Presence Core 24G (Matter, SNWF-06P24)

An inexpensive fix for lights that go out on you

The job is familiar. A motion sensor switches the lamp off while someone reads, types or watches a film, because sitting still looks like an empty room. SONOFF says its 24 GHz radar picks up the small movements of breathing, so a desk, reading chair or kitchen table can stay occupied without anyone waving an arm. A light sensor covers the other half of most lighting automations: switch on only when the room is actually dark.

The price is what makes it worth a look. At about $25, £23 or €25 from SONOFF's own stores, it costs less than any other presence sensor Matterhome reviews that joins Matter without a brand hub. It connects to Apple Home, Google Home, Alexa, SmartThings and Home Assistant directly over 2.4 GHz Wi-Fi, so the only infrastructure it needs is the Matter controller your platform already uses, such as a HomePod, Nest speaker, Echo or SmartThings hub. There is no SONOFF bridge or Thread border router to add.

Check the model number before you order. SONOFF sells a Zigbee sensor under the same SenseGuard Presence Core 24G name, the SNZB-06P24, at about the same price, and it reaches Matter through a SONOFF Zigbee bridge. The Matter version reviewed here is the SNWF-06P24.

Matter gets the answer, SONOFF's tools get the tuning

Paired over Matter, the sensor reports two things: occupied or clear, and a light level. That covers the automation most buyers want: lights on when someone is present and the room is dim, off a few minutes after they leave.

The adjustments that make radar behave live elsewhere. The 4 m detection range is split into seven distance bands that you switch on or off, for example to ignore a doorway at the far side of the room. A calibration routine learns fixed sources such as a fan or air conditioner and filters them out, sensitivity moves six steps either way, and the hold time before the room reports empty runs from 15 seconds to almost 12 hours. Zones, calibration and sensitivity stay out of Matter apps, though Home Assistant's Matter integration does show the hold time. You set them in the eWeLink app or in OpenEdge, a console the sensor serves to a browser on your home network, and the sensor can stay connected to both while it is paired with your Matter platform.

That split works well for a single room. Set the zones and calibration once, and Apple Home or Google Home only needs the occupied signal. It also means the zones are masks: your Matter app cannot tell the sofa from the desk. If one open-plan room needs separate signals for different areas, Shelly Presence Gen4 sends its zones to Matter, at more than three times the price.

Home Assistant owners get more than the Matter pairing. OpenEdge can switch on MQTT with Home Assistant discovery, a WebSocket connection, and a switch that disconnects the sensor from SONOFF's cloud. That makes it a good fit for a local-first Home Assistant setup as well as for an Apple or Google home.

Alexa is the weakest platform for it. Amazon maps Matter occupancy to its motion sensor and has no interface for a Matter light sensor, so Alexa routines get presence but no light-level condition.

Where it fits, and where it doesn't

The sensor needs constant USB-C power at 5 V and 1 A, and it has no battery. The box holds a USB-A to USB-C cable, the magnetic base, an adhesive pad, screws and cable clips, but no power adapter, so budget for one if you don't have a spare. The cable then decides placement. The sensor belongs 1 to 2 m above the floor, aimed at the chest of the person it is watching, standing on a shelf or desk or fixed to a wall. That height limit rules out the ceiling.

The range suits a study, reading corner or small living room better than a large open space. SONOFF rates it at about 4 m across 120 degrees, with a person sitting still detected best within 3 m of its front.

Two limits rule out common jobs. SONOFF says the sensor cannot reliably detect a sleeping person, so it is the wrong choice for keeping a bedroom occupied overnight or holding the heating while someone sleeps. Neither the zones nor calibration can exclude something that moves around the room, so a pet or a robot vacuum can register as presence. For pets, the only remedy offered is to tilt the sensor upward, away from where they walk.

Cheaper than the Meross, by less than the sticker suggests

The closest rival is Meross MS600, another USB-powered presence sensor that joins Matter over Wi-Fi. Its sticker price is about $16 higher in the US, but Meross includes the power adapter and free delivery. A single SenseGuard falls below SONOFF's free-delivery threshold and arrives without a plug, so the real saving is smaller unless you have a spare USB adapter or are ordering other SONOFF gear. MS600 also adds an infrared motion sensor and a longer rated range for a seated person. SenseGuard answers with the local console, MQTT and the cloud switch.

If a cable can't reach the place the sensor needs to watch, buy a battery sensor instead. Aqara FP300 and Meross MS605 both run on batteries over Thread, so they need a Thread border router, and FP300 adds temperature and humidity readings.

For a Wi-Fi Matter home that needs one presence signal in a study, office or living area, SenseGuard Presence Core 24G is the one to buy first. Spend more only for battery placement or separate zones in your Matter app, and keep it out of the bedroom.