A project log for J1772 Hydra

Charge two electric vehicles at once

nick-sayerNick Sayer 08/03/2020 at 16:340 Comments

This project has been pretty stable. The only two changes I'm contemplating are adding an MCP9808 temperature sensor to the board for over-temp detection and adding the OpenEVSE II AC voltmeter.

The problem with either of these options is that the Mega328 is running out of space in flash. Adding either feature would require more code, and I'm not sure it would fit.

Moreover, it's hard to squish the voltmeter onto the AC board, and would also require freeing up an ADC pin on the 328, which means firmware changes (because something non-analog would have to move from port A to port C) which would not be backwards compatible.

For now, I'm probably going to at least add the MCP9808 hardware and perhaps kick the can of software support for it down the road, but I'm probably not going to add the voltmeter.