Telly
Thinks s/he gets paid by the post
- Joined
- Feb 22, 2003
- Messages
- 2,395
I don't get it. Our 1500 watt decades-old hair dryer (some call them a "blow dryer") gave it up. Its motor speed became position-dependent. Performed a post-mortem on it. The brushes in its DC motor wore away. Had a diode bridge feeding it, to use a cheap DC motor on AC.
So buying a new hair dryer shouldn't be an issue, probably a zillion of them out there. But found something strange. Almost every hair dryer, except for a few small travel ones, now are 1875 watts, instead of 1500 watts, which used to be the standard max wattage.
I have an issue with a 1875 watt device, which would be the max power on high heat. 1875 watts at 120 volts is 15.625 amps. In addition, our line voltage is higher, usually 124-125 volts, which with a resistive load like a heating element, would result in a slightly higher current than that.
A regular outlet is rated at 15 amps. And usually the branch circuit feeding it is 14 gauge wire, 15 amps max rated. Often, 120 volt branch circuits in kitchens are 12 gauge 20 amp rated, but the outlets are 15 amp, idea being the max 20 amps branch capacity is spread over more than one 15 amp outlet.
A true 20 amp outlet can accept the typical 15 amp max plug, and also accepts the special 20 amp plug, which has its neutral prong at 90 degrees to the hot prong.
Obviously, the 1875 watt hair dryers have the regular 15 amp style plug. So on "High", they by definition overload the outlet itself, and if the branch circuit is sized for 15 amps, it too.
This overcurrent situation is not going to trip a breaker, as they require a higher current for a longer time to trip. Seems like a bad idea to me, eating into safety factor that has been the standard for years.
Am I missing something here? It makes no sense to me. Getting a new hair dryer rated 1875 watts, and telling DW not to use it on the highest heat, isn't a viable solution to me.
So buying a new hair dryer shouldn't be an issue, probably a zillion of them out there. But found something strange. Almost every hair dryer, except for a few small travel ones, now are 1875 watts, instead of 1500 watts, which used to be the standard max wattage.
I have an issue with a 1875 watt device, which would be the max power on high heat. 1875 watts at 120 volts is 15.625 amps. In addition, our line voltage is higher, usually 124-125 volts, which with a resistive load like a heating element, would result in a slightly higher current than that.
A regular outlet is rated at 15 amps. And usually the branch circuit feeding it is 14 gauge wire, 15 amps max rated. Often, 120 volt branch circuits in kitchens are 12 gauge 20 amp rated, but the outlets are 15 amp, idea being the max 20 amps branch capacity is spread over more than one 15 amp outlet.
A true 20 amp outlet can accept the typical 15 amp max plug, and also accepts the special 20 amp plug, which has its neutral prong at 90 degrees to the hot prong.
Obviously, the 1875 watt hair dryers have the regular 15 amp style plug. So on "High", they by definition overload the outlet itself, and if the branch circuit is sized for 15 amps, it too.
This overcurrent situation is not going to trip a breaker, as they require a higher current for a longer time to trip. Seems like a bad idea to me, eating into safety factor that has been the standard for years.
Am I missing something here? It makes no sense to me. Getting a new hair dryer rated 1875 watts, and telling DW not to use it on the highest heat, isn't a viable solution to me.