Cao Gadgets wireless smart tags

About a year ago, as I was considering various ways to save energy, I thought about installing air duct dampers at various points of my A/C system to control temperature with more precision throughout the house (rather than just the 1- or 2-zone systems common today). My plan was to control these dampers with an Insteon I/O Linc so I could manage all the zones via Insteon, such as “shut off the A/C vent in the guest room when it’s not needed”. I’ve since implemented a whole-house energy saving plan by automatically powering down the A/C when I’m not home, but this idea was to go above and beyond that: I was going to have a thermostat in every room to allow for much more precise control of heat and A/C.

That’s when I found the Cao Gadgets wireless smart tags. They are these tiny, neat little devices that measure temperature and motion, and report that information up to the cloud for alerting purposes. So for example, you could put one in your refrigerator to alert you when the door is open or the temperature rises above a critical level.

Unfortunately, aside from the difficulty of installing those dampers and cost of executing such a plan, the show-stopper was that the temperature sensor just wasn’t accurate enough. I’ve tried repeatedly to calibrate these guys by placing them next to the thermostat for a while to get them all at the same temperature:
… but after calibrating them all to the same temperature and letting them sit for a while, they continue to skew by up to 2 degrees in either direction, which makes them pretty useless for thermostat duties, because in that context 69 and 73 degrees are quite different.

Still, they’re neat little tags that can be purchased here, but consider them more useful for their motion-sensing purpose (such as detecting whether a garage door, refrigerator, or gate is open) than temperature-sensing.

Posted by Matt Chiste
March 12
2 comments on “Cao Gadgets wireless smart tags
  1. Ross says:

    I have a similar batch of tags with similar results. I have had them for about a year now and not only are they not entirely accurate, they tend to lose their signal periodically. Additionally, capturing data on a frequent basis really starts to drain the battery. The moisture sensor showed promise, but the battery is essentially irreplaceable and again, the frequency at which you’d want to monitor moisture to check for a leak is pretty high. They are fun to play with but not something I’d hang my hat on, unfortunately. There are newer versions out now that look more polished, but based on my experiences I probably won’t be buying anymore. Too bad, because if they worked I would buy a bunch more.

    • Matt Chiste says:


      Thanks for the feedback – I recently got an email about a new Kickstarter campaign they are running:

      Two interesting points from the campaign:
      1) They’re announcing a full thermostat with no interface to compete against Nest – arguing that your phone already has all the interface you need.
      2) They’re touting their new sensors as accurate with +- 0.4 degrees C, which could finally make them useful for this type of application.

      I agree with you though; I’ll likely sit out this generation but will post again if I find any alternatives or eventually take the plunge again with Cao.

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