Showerthought: That time a customer's 'faulty' motion sensor took me 4 hours to figure out

Turns out their new cat was a perfect 8-pound trip weight for the pet-immunity setting, which I only realized after the third service call when I saw the little guy jump right onto the console shelf.

4 comments

4 Comments

wyatt1351mo ago

Pet immunity is usually based on the heat signature size, not just weight. An eight pound cat should absolutely NOT set off a properly tuned sensor. The real issue was probably where the cat was jumping, like right in the sensor's direct line of sight. The installer likely set the pet immunity too low to avoid missing real threats. That's a classic setup mistake that creates these exact callbacks.

paige_owens51mo ago

The Bosch 500 series manual says pet immunity works up to 40 pounds for dogs. But you're right, it's about the heat mass and movement path. A cat jumping on a counter crosses the sensor's lower zone, which often isn't pet immune at all. That's why mounting height and the exact walk test matter more than the weight setting.

pat_stone1mo ago

I mean, maybe it's just me but I've seen cats set them off all the time.

drewr151mo ago

Nail that walk test and you solve most false alarm headaches.