I picked up a few of the lots of 10 Iris V2 motion sensors of ebay. While I primarily got them for motion sensing, I also hoped to use them to keep track of temperature changes in different rooms throughout the house, outside, and even in the attic.
As advertised, some look used (dirt on one, superficial cracked plastic on another), but all ten came with batteries (two different brands), all reading 100%, with a plastic tab in place keeping them powered off.
One, unfortunately, had a very loose battery (too loose to make contact; rattled inside before I even opened it) and when I removed the battery, the smaller contact/tab that holds it fell out. When I tried to bend the piece that remained, that broke, too! Warning to others: don't try bending these tabs, they are apparently very brittle and will NOT bend!
The remaining nine paired fine (although I've probably exceeded how many I can add per wired Zigbee device; I'll know what to look for if they start going offline). I have them lined up on my desk for now. All nine are tracking motion (and lack of motion) wonderfully; reporting motion almost immediately and lack of motion in about 30 seconds.
However, temperatures are all over the place!
I plan to get some graphs setup, but in the meantime:
After being connected for 15 minutes, they read:
76.03
84.12*
71.82
74.25
81.38*
75.94
74.88
74.52
74.56
*That 81.38 and 84.12 haven't budged, so they're apparently faulty. Any ideas to them back to life?
An old Go Control motion sensor says this room was 71. An old analog HVAC tech temperature probe I have read about 72. I'd argue 72 is probably a good reference temperature, so I set them to offset to 72 from their current temps and moved them to the garage to see how the reported temps align in that area.
After about ten minutes, the Go Control was at 94. The analog temperature probe, 91.
The Iris, after the same amount of time (and with the offset applied earlier), were lagging far behind.
77.12
84.12*
81.22
80.66
81.38*
82.17
82.22
81.63
82.8
After an hour(!), Go Control 96, probe still at 91, most of the Iris were catching (or caught) up:
88.33
84.12*
85.3
89.37
81.38*
90.69
89.96
89.39
90.14
Temperature accuracy is a little disappointing ... and slow. How are they so slow at coming to temp? Looking at the logs, they're updating with temp changes a little as 1.5 degree (and less in some instances), so it seems like the sensor itself it that slow:
2019-08-18 17:54:03.865 Motion Sensor 03 temperature is 75.78°F
2019-08-18 17:49:03.140 Motion Sensor 03 temperature is 74.24°F
2019-08-18 18:30:29.773 Motion Sensor 06 temperature is 88.71°F
2019-08-18 18:25:28.704 Motion Sensor 06 temperature is 87.79°F
I may message the seller about the three that are currently aren't working properly (unless his ad stated as is, I need to double-check), but I have ten more to unpack plus a bundle of ten contact sensors also on the way.