The objective of this project is to design and build a lightning detector as part of a wider set of our smart home weather monitoring.
Part of the reason for doing this is simply curiosity about how often and when lightning occurs around our home but we also interested in understanding if it can be used as part the wider understanding of the weather around out home and to see if it can be used to take preventative action.
As we only require one of these sensors, we have built it using Vero board. This shows it with an LED indicator but this is now used to drive an opto-isolator. We have also added a 5V dc regulator to enable it to be powered from the 12V dc source.
Our lightning sensor is generically modelled like all sensors in our home. It is a 'Binary' sensor type with values of 'On' or 'Off'. For now we are not interested in the duration of each lightning strike, so our focus is on the transitions of state from Off to On. Our software will report and notify us of new lightning strikes, e.g. only if one hasn't been seen for 24 hours prior to this new strike. It will then count strikes seen in each 10 minute segment and report these strike counts (if greater than zero).
Detected lightning is another of the weather events tweeted by our smart home: