Final answer:
Electrical power tools require a three-wire cord grounding and various safety devices to prevent hazards. This includes grounding, GFCI, circuit breakers, and proper plug and outlet connections for safety compliance.
Step-by-step explanation:
Electrical power tools must be grounded by a three-wire cord, properly insulated, powered by a low voltage transformer, or powered by self-contained batteries. These measures are essential for electrical safety, preventing thermal and shock hazards. The three-wire system is significant because it includes a live/hot wire, a neutral wire, and an earth/ground wire, grounding the neutral wire and the case of the appliance to avoid potential electrical shocks. Further safety devices such as circuit breakers, fuses, ground fault circuit interrupters (GFCI), and isolation transformers help prevent electrical accidents by interrupting excessive currents or insulating the device from the power source to prevent shocks. Additionally, standard three-prong plugs and outlets ensure these safety systems function correctly by only allowing insertion of the plug in one direction, consistent with the wire color-coding which varies by region.