The wiring from the fuse box or breaker panel to the outlet might be #12, but lamp cord is not that fat. A heavy duty extension cord might be #12, but I've seen that only in long heavy duty cords for outdoor use. Most lamp cords and short extension cords for indoor use are #16 or #18.I Thought a Lamp Cord that goes into an OutLet in the USA is 12 AWG?
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