There are a couple smaller things I've been thinking about. One is an energy monitor for DC systems. Basically, it would be have two Anderson Power Pole connectors, one in and one out, a current sensor, and a microcontroller with RS485 for comms. It would do things like give instantaneous voltage, current, and power, and track accumulated energy (watt-hours) and maybe charge (amp-hours). It would work for 12, 24, and 36 VDC nominal systems. I had actually attempted something like this before, but this would be smaller and more compact. Yes, they're commercially available, but this would be more fun.
The other things is a low voltage (again, 12, 24, or 36 VDC nominal) load timer. Basically, three load switches, a microcontroller, RS485 comms, but also a real time clock. Just like a standard timer – set date and time for on/off, or duration.
These are relatively smaller than other things I've had in my queue as far as projects, but they're neat, kind of useful, and a great excuse to design more printed circuit boards.
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