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Meross
Meross MS605 Matter over Thread presence sensor with mmWave radar, PIR, and light sensor
Presence sensor

Meross MS605

Meross · MS605

The Meross MS605 is a smart presence sensor built on Matter over Thread, designed to detect human presence more accurately than a traditional PIR sensor. It combines 24 GHz mmWave radar, infrared detection, and an ambient light sensor to reduce false positives and keep automations running even when someone is sitting still or barely moving. Unlike many WiFi presence sensors, the MS605 works over Thread and is powered by the included CR123A battery. To add it to platforms such as Apple Home, Alexa, Google Home, SmartThings, or Home Assistant, you need a Matter-compatible ecosystem and a Thread Border Router. Initial setup is done over Bluetooth from the Meross app, but after that it can operate locally on the Matter platform you choose without relying on WiFi 2.4 GHz or a Meross hub. The sensor can detect motion up to 6 meters away and presence with greater accuracy up to 4 meters. In addition, the Meross app lets you split detections into three customizable zones, which appear as separate sensors in third-party platforms, making it possible to build more precise automations by distance or area. Its adjustable 90-degree bracket and 360-degree rotation make it easy to install on a wall, ceiling, corner, or flat surface. It also features IP67 certification, an operating range from -20 °C to 60 °C, and an advertised battery life of up to 3 years with the CR123A battery.

BluetoothThread

Pros

  • Matter over Thread
  • No WiFi 2.4 GHz required to operate
  • Compatible with Home Assistant via Matter
  • Compatible with Apple Home, Alexa, Google Home, and SmartThings
  • 24 GHz mmWave radar
  • Combines radar, infrared, and light sensor
  • Detects presence even with subtle movement
  • Three customizable detection zones
  • Each zone can appear as an independent sensor in third-party platforms
  • Powered by included CR123A battery
  • Advertised battery life of up to 3 years
  • IP67 resistance
  • 90-degree adjustable bracket and 360-degree rotation
  • Can be installed on a wall, ceiling, corner, or flat surface
  • Operating range from -20 °C to 60 °C

Cons

  • Requires a Matter-compatible Thread Border Router
  • Does not work over WiFi
  • Not Zigbee
  • No MQTT or ESPHome
  • Automations inside the Meross app require a Meross hub planned for 2026 Q3
  • Alexa does not currently support the light sensor according to the official specs
  • Advanced zone setup is done from the Meross app
  • Actual accuracy can depend heavily on the sensor's placement and orientation

Compatibility

Home AssistantMatterAlexaGoogle HomeApple HomeSmartThings

Specifications

ModelMS605
TypeMatter over Thread presence sensor
Main protocolMatter over Thread
Initial setupBluetooth via Meross app
ChipsetNordic according to the official specs
Detection technologymmWave radar, PIR infrared, and light sensor
Radar frequency24 GHz ISM
Motion rangeup to 6 m
Accurate presence rangeup to 4 m
Detection zones3 customizable zones from the Meross app
Light sensoryes, with reporting to Matter platform
Batteryincluded CR123A
Advertised battery lifeup to 3 years
Protection ratingIP67
Bracketfoldable 90 degrees and 360-degree rotation
Installationceiling, wall, corner, or flat surface
Button1 button
LED1 status LED
Antennaintegrated PCB
Wireless Standards listed in specsBluetooth 4.3
System requirementsiOS 16.1 or later or Android 8.1 or later with Bluetooth 4.2 or later
Dimensions77 x 35 x 48.5 mm
Operating temperature-20 °C to 60 °C
Operating humidity20-95% RH non-condensing
CertificationsCE, FCC, IC, and WEEE
Power supplyPila CR123A
Neutral wire requiredNo