Looking for a cheap and easy way to track your power usage? Hackers keep trying to introduce cheap alternatives that can be made using everyday items. Kalle has hacked a cheap Chinese power plug that is easily hackable. These power meter cost you as less as the first-generation Kill-a-Watt, but they directly put out digital data. Kalle’s power meter features a non-US plug, but the meter is available at retail outlets (eBay, Alieexpress, etc) with a 3-prong US plug and 120v rating.
Kalle opened the cover of a logic analyzer and discovered that the meter constantly streams voltage, current, and power data from the measurement board to the display board on a SPI-like bus. The ribbon cable’s clock and data bus lines are clearly labeled. Kalle reversed the code and developed an Arduino sketch that parses the stream, making it a lot easier to integrate this power meter into your next power monitoring project.