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Got told I was mounting motion sensors too low
A guy I worked with in Minneapolis last summer pointed out I was mounting motion sensors at 6 feet. He said that's fine for pets but misses the high heat signature from a person's torso. I moved them up to 7.5 feet and suddenly my false alarm rate dropped by half. Now I check the ceiling height first and adjust every sensor based on that. Anyone else catch themselves sticking to old habits just because that's how they learned it?
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laura_knight547d ago
Man I never thought about the heat signature part... 6 feet just seemed standard to me too because that's what my first boss taught me. What really got me was when I started thinking about kids and pets that could trip them if they're too low anyway. The 7.5 foot rule makes total sense for catching that core body heat but it also keeps the sensor out of easy reach for little ones. Makes me wonder how many false alarms could be solved just by moving stuff up a foot and a half.
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hayes.elliot7d ago
Yeah, I see it differently though @laura_knight54. Moving it up just means you're now missing short adults or people in wheelchairs instead of kids and dogs.
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Good point about heat signatures, but I'd push back a little on the 7.5 foot rule being a catch all. In a lot of residential builds around here the ceilings are only 8 feet, so you're basically putting the sensor right at the top of the door frame. That can actually miss someone's torso if they walk right under it, especially with a vaulted ceiling throwing the detection cone off. I've had luck splitting the difference at 6.5 feet, keeps it above pet range but still low enough to catch a person's core heat without needing a perfect angle.
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