NYC Doc said:

Recently, while perusing Ebay, I noticed an auction (actually several)

for

a

2800 watt "Volcano" hair dryer. This was 800 more watts than I had ever

seen. My initial reaction was that it couldn't be possible because this

would lead to triggered circuit breakers. So I purchased a hair dryer in

addition to a non-contact current meter.

Using a split extension cord, it was registering 9.8 amps, slightly less

than my 1800 Conair dryer. So, it is safe to say that [most of the]

voltage is in phase with current? I would assume that 99% of the energy

goes to the heating element.

If this is this case, then the power should be

9.8 * 2 *120 (approx) * 0.99 ???

= 2156 ?

The total wattage is the current times the voltage. 9.8 *120 = 1176 watts.

I don't know how you managed to put the 2 in your equation. The dryer is

purely resistance (not counting the motor which should be a very small draw)

so all the current would be converted to heat.

If it was a 2800 watt unit , it would draw 23 amps. That is 3 more than

than the wall sockets are rated at the most. I doubt that any dryers would

really be rated over 1500 watts if that was their true value. That is

almost the limit of most house circuits, especially if they have anything

else on them.

I did a quick check of one at the house. It is rated 1875 watts. It

actually uses 11 amps on the highest heat. The motor uses about 1.5 amps.

This only leaves 9.5 amps for the heater. At most it could be rated 120 *

11 = 1320 watts. This is for the motor and heater.

I think they just pull numbers out of the air for the dryers. I guess they

could multiply it by 1.4 to give it a fake peak wattage instead of a RMS

wattage. That would make it about right.