Ring Alarm Motion Detector vs Shelly Blu Motion

The Shelly Blu Motion edges ahead overall on price and its added light (lux) sensor, making it a strong pick for fast indoor lighting automations in a Shelly and Home Assistant setup. The Ring Alarm Motion Detector carries a higher owner rating and is the better choice as a pet-friendly Ring Alarm security sensor.

Purpose. The Ring Alarm Motion Detector is a security sensor for the Ring Alarm system (or a Z-Wave hub), tuned to ignore pets up to about 50 lbs, while the Shelly Blu Motion is a compact Bluetooth lighting sensor with a lux sensor that relies on a Shelly bridge for Home Assistant, Alexa and Google.

The Shelly Blu Motion, thanks to its built-in lux sensor for dark-only triggers, fast response and Home Assistant, Alexa and Google support. The Ring Alarm Motion Detector is aimed at security alerts within Ring Alarm rather than smart-lighting scenes.

Yes, both need support and are indoor-only. The Ring Alarm Motion Detector needs a Ring Alarm base station or a Z-Wave hub, and the Shelly Blu Motion needs another Shelly device or a BLU Gateway to bridge Bluetooth to WiFi. Neither is weatherproof.

Buy the Ring Alarm Motion Detector if you run a Ring Alarm system (or a Z-Wave hub) and want a well-rated, pet-friendly security sensor. It reliably ignores pets up to around 50 lbs while catching human-sized motion, with long battery life.

Buy the Shelly Blu Motion if you already have Shelly hardware, use Home Assistant, and want a small, low-cost, fast sensor with a lux sensor and up to five years of battery life for lighting automations. It is the value lighting pick here.