This is something I’ve been eager to start work on for months. It will be a device that sits between your car’s battery and a powered device (such as a radio transceiver for my fellow ham radio operators). It will detect the voltage drop that accompanies the engine shutting off, at which point it will perform a countdown until it disconnected the powered device.
The idea is to ensure high-current systems that require direct battery connection to be shut down automatically when the vehicle is turned off, thus preventing the battery from being drained.
The chief goals of the module are:
- Battery disconnect based on detection of a voltage drop (programmable threshold)
- Battery disconnect based on errant current draw (programmable threshold)
- Programmable timer that gets activated after the threshold is met
- At least 20A max current
- Live voltage/current/power readings on the LCD during normal operation
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The project is in its very early stages. I have gotten everything wired together and the MCU is able to control the necessary components. The next steps are to complete the firmware, revise the PCB design, create an enclosure, and perform plenty of testing!
