Hellow fellow Arduino members,
Currently I'm investigating the setup of a table with 3 coffee machines. I want to count the number of times the user requests a cup of coffee, and was thinking of doing this by placing a hall effect sensor over the cable to measure changes in the magnetic field around it. This would be a regular 220 V cable (Europe) that goes into a power socket.
This sensor would be connected to an Arduino with integrated WiFi. Each time the power peaks, I'd a +1 to the database.
In my head this setup would work, be it not that accurate as one of the machines sometimes rinse and clean itself automatically. However, it's more of a gimmick project, so not real accurate data is needed.
But maybe there's better advice on thinking about hardware for this. Looking forward to hear your ideas!
/edit PS: all ideas welcome, still need to buy everything