All: Model S charges on our antique 100 amp (50 amp breaker) service. Pretty soon, we hope, big brother Model X 12121 will be sharing the charging. Issue: if they both are charging at the same time, I think we will have overload and our old Zinsco breaker either will trip or it will be Ms. O'Leary's cow all over again....So, the cars have to charge serially. I do not want to get up at 4 a.m. and switch the plug, so I want to plug both cars in and go to bed. One car can charge, and then the other. If the timers are set correctly , no problem. If not, there could be one. Query: do the cars talk to one another to ensure there is no overload? If not, they should because I am certain we are not going to be the only ones with this issue, and it could be a problem....Tailwinds! John MS 41448