Plug Bug: Charger Control Updates
I made some updates to my charger control project. I discovered my EVSE didn’t like the way I was testing for the proximity switch on the plug latch to be closed. Whenever the Arduino was on, I had the 5v line running through a 2.yk resistor to ground in order to detect it not plugged in. There was another line going into the Vehicle J1772 inlet. That goes into a circuit inside the plug that looks like this:
What happens here is the resistance to ground changes once the J1772 plug is plugged in, and changes again once the latch switch is engaged. The problem I was having is that the ground inside the switch is shared with the 240 AC ground, and also tied to the vehicle ground. The EVSE was noticing that there was some voltage coming off the ground, and after a certain amount of time for not charging would go into a fault state. This caused me to not properly do timed charging!
So, I switched my proximity detection around to use an Arudino digital pin to feed the 5v only when I want to test for the proximity. I removed proximity testing when the timer was not actually wanting to charge, and it fixed this problem.
I also tweaked some of the menus to work a little better. Source is on github.
