Smart Home — FAQ
What's the real-world difference between PIR and mmWave sensors?
PIR detects moving heat sources—great for walking detection but fails when you're still. mmWave radar senses micro-movements like breathing, keeping lights on while you read. For basic hallway lighting, PIR suffices. For occupied rooms, mmWave prevents annoying timeouts.
Do budget WiFi sensors work without internet?
Most require cloud servers for app notifications and automation. Without internet, Alexa/Google integration fails. Some support local MQTT for advanced users. Zigbee sensors offer true local control through hubs like Home Assistant, working offline during internet outages.
Is Matter support worth the premium for budget buyers?
Matter future-proofs your investment across platforms. If you plan to switch from Alexa to HomeKit or add new ecosystems within 3 years, Matter saves replacement costs. For static setups, WiFi sensors deliver equal performance for less money today.
How pet-friendly are 'pet immune' sensors really?
Pet immunity works by ignoring movement under a certain weight threshold—typically 55-80 pounds. Sensors must mount at specific heights (6-7 feet) facing away from pet climbing paths. Large dogs jumping on furniture still trigger false alarms. For multiple pets, consider mmWave with AI filtering.
What's the total cost of ownership for a budget sensor?
A $25 WiFi sensor with 12-month battery life costs $30 over two years (including $5 battery). A $40 Zigbee sensor with 5-year battery costs $40 over five years. Add $40 hub cost if you don't own one. Calculate per-year cost, not just purchase price.
Can I use these sensors outdoors?
None of these budget sensors are weatherproof. Outdoor use voids warranties and causes false triggers from rain, insects, and temperature swings. For outdoor motion detection, budget $40-60 for IP65-rated Z-Wave or dedicated outdoor WiFi sensors with proper seals.
