ABSTRACT
Older readers will remember the glory days of beautifully engineered power tools with aluminum cases. Those case were all tied to the AC mains ground. Any internal failure would short to the conductive case, and thus to the mains ground, blowing the fuse. Today these tools are all encased in plastic and often have no ground connection to the mains. The nonconductive case will not conduct a short circuit to the user, so although there’s no safety ground, the user is already protected.
