From time to time, when doing service upgrades on older homes and I remove the panel cover, I notice along with the original 60A service wires terminated at the Main fuses, there are 2 #10s coming inside the same conduit and rolled up inside the panel with taped ends.

What was the purpose of this?

Sandro,

They were used for Flat Rate Utility owned Electric Hot Water Tanks . . . in the Golden Days . . .

Tony Moscioni