SimpliSafe Motion Sensor

The SimpliSafe Motion Sensor Gen 2 is a passive infrared (PIR) motion detector designed to protect entire rooms within the SimpliSafe security ecosystem. With a 35-foot detection range and 90-degree field of view, it covers substantial areas while minimizing blind spots.

The standout feature is the Pet Mode—using advanced PIR sensing and detection algorithms, the sensor distinguishes between humans and pets up to 60 pounds. You can toggle between Standard Mode and Pet Mode directly in the SimpliSafe app, along with adjusting sensitivity levels.

The sensor mounts on walls approximately 5 feet off the ground using included adhesive or screws. The larger 1.5-inch dome (compared to Gen 1's 1-inch dome) provides improved detection capabilities. A CR-123A lithium battery provides up to 4 years of operation.

When motion is detected, the Base Station can announce which sensor was triggered and/or sound an alarm. For discreet monitoring, Secret Alerts send notifications to your phone without audible alarms.

Common false alarm triggers include direct sunlight, heating vents, moving curtains near radiators, and pets getting too close. Proper placement away from heat sources and HVAC vents is critical. Some users report sensors randomly stopping motion detection without error messages.

Home Assistant integration works through the official SimpliSafe integration with 30-second polling intervals. The system works with Alexa and Google Assistant for arm/status commands only—no individual sensor control. Apple HomeKit requires third-party bridges.

The Gen 2 sensor replaces the original Gen 1 model with improved pet immunity and an additional 5 feet of detection range.