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Sensor Accuracy

We use inexpensive DHT22 temperature and relative humidity sensors, so we don’t assume they are reliable. Instead we compare them with each other and with the most common off-the-shelf devices we see in use, Lascar EL-WIN-USB loggers. Our Lascars claim accuracy of 2.25%RH in the range 20-80% RH. Years back, we had some engineering students […]

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Electricity monitoring

One of our community groups has already asked us about electricity monitoring. This is something we’ve done in the past using equipment that utility companies were giving out for free about ten years ago. We don’t have many monitors – although they are still available from dusty cupboards everywhere, and sometimes, rather expensively, on ebay. […]

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Our monitor design

We’ve spent several months now designing and testing the sensor devices before settling on the final design. It’s not something our participating groups or engineers need to know about, but there are some people who want to know how they work, and why they are the way they are. There are two types – standalone […]

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Monitoring devices

Being able to see what the temperature of a space does over time can throw up some real surprises. Like the proverbial tree in the forest, who can be sure what happens in the night when no one is around? One part of HeatHack’s programme involves placing a small device in the building that measures […]