Off grid charging my 2020 Bolt

[Montinhi]

I have been charging my 2020 Bolt on my off grid photovoltaic 240 V system at 10 Amps using a portable charging unit. I was thinking that it would be nice to have an automatic control that would turn off my charger when the charge level of my home system dropped below 80% and then would switch back on when the system was above 80%. Any ideas? I have been very happy with my charging system otherwise. I am limited to charging during the day, but am often home during the day. My backup vehicle is a 1995 Mercedes Benz that burns waste vegetable oil sourced from our local restaurant.

 

[tdiguy]

Pretty cool to see someone else that uses veggie oil for fuel. I did that for a while years ago when i had a 01 vw jetta tdi.

 

[JoeS]

Presumably, your off-grid system is charging a fairly robust battery bank: is it lead-acid or some lithium flavor? What output do you have from that BMS; i.e., is there a signal available you could use to energize/de-energize a contactor? What percentage of your PV power output goes to the 240vac 10A charger? If voltage is used as a SoC monitor, will turning off the charger result in an immediate system voltage increase? Whatever control you end up with, be sure to include some hysteresis; i.e., turn off charger at 80% but enable it at some conservatively higher number to avoid oscillation.