The Electrical Code

220.54 Electric Clothes Dryers — Dwelling Unit(s). Basically we begin here with saying every electrical clothes dryer is a minimum of 30 amp. Those dryers that require more say it on the name plate. In todays residential electric clothes dryer because of efficiency have stayed at 30 amps for years. In 1915 the first electrical clothes dryer was invented. In 1930 the advent of a thermostat and rotating drum to move the clothes around was introduced. Not until the 50’s was timers where introduced. Then in 1970’s the gas dryer was introduced and it came with much more efficient specifications. As far as what I was able to find those early electric dryers had a spec of 50 amps at 220 volts. Then it went down from there. Only the rich had services in there house that could handle those loads but it came fast and by 1971 44% of the US households had a dryer in them. A far cry from what it is today.

“The load for household electric clothes dryers in a dwelling unit(s) shall be either 5000 watts (volt-amperes) or the nameplate rating, whichever is larger, for each dryer served. The use of the demand factors in Table 220.54 shall be permitted. Where two or more single-phase dryers are supplied by a 3-phase, 4-wire feeder or service, the total load shall be calculated on the basis of twice the maximum number connected between any two phases. Kilovolt-amperes (kVA) shall be considered equivalent to kilowatts (kW) for loads calculated in this section.”