We have a 50 amp / 240 volt outlet in our garage for an electric car charger. We would like to use this power for snow melting our driveway in Massachusetts so as to avoid needing more power to be added to the house. We would never charge the car and snow melt at the same moment of time. I would have thought there would be some sort of manual switch that would allow me to select between "charge car" and "snow melt," but one electrician said that if we attach the snow melter, we could never charge the car. Each one is required to have its own dedicated circuit, and we would have to add power to the house. If this is the code? Why? Why can't I just be allowed to choose ?
To be clear, my existing setup is two 50amp breakers in a 100 amp subpanel dedicated for two electric cars.
I gather I could theoretically have four 50 amp breakers where I now have two: two for the electric cars, and two for the snow melters. It would all be legal, if I got two generator interlock kits and each one pairs two of the 50 amp circuits, insuring that I could never use more than 100 amps at a time. Is that the idea?
Any reason why these interlocks couldn't be placed by the existing 100amp subpanel (shown here in the photo)?