(directly = Hot, L-shape = Neutral, Round = Ground) Appliances with 110 volt that pull more than 15 amps require a 30 amp socket with 10 measure cable and a Nema 5-30 plug. A regular 3-prong cord is used if 110-120 volt appliance is under 15 amps.
(Hot is actually the verticle and right) Appliances with 240 volts need a 20 amp socket with 12 measure wire and a Nema 6-20 plug.
Pictured left to right: Heavy duty 30 amp 110-120 volt Nema 5-30 Plug, Standard 20 amp 220-240 volt Nema 6-20 Plug, and a typical 110 volt plug as entirely on most electronic devices. Read More