On Jan 28, 12:26*pm, blueman wrote:
"Existential Angst" writes:
"Bob F" wrote in message
...
Existential Angst wrote:
"E Z Peaces" wrote in message
...
terry wrote:
Our very conventional old style tumble dryer timer runs for some 45
minutes per load.

With *heater cutting in and out (estimating it's on say 80%?).

Heater elements are either 3000 watts or maybe 4500, haven't had
this one apart yet, since I got it in exchange for a dozen beer!

Our domestic electricity costs a little over 10 cents per k.watt hr..

So one load of clothes 45/60 x 0.8 a cost of electricity = 0.75 x
0.8 x 0.12 = 7 cents per load.

Occasionally it is necessary to run a 'heavy' load, towels and
blankets etc. part of a second run.

So maybe that could be say 12 to 15 cents per load. In summer we
hang bedclothes and towels on outside lines.

Weigh the load going in and coming out. *Each pound lost takes
0.285kWh. Some cotton garments are very heavy going into the dryer,
and they probably cost a lot to dry.

You would have to add the cost of turning the drum and blowing the
air. I could get the wattage by timing my power meter after
switching off all my other circuits and starting a load in with no
heat. *After the load dried, I'd run it without heat again and check
the wattage again. *I'd take the average and multiply it by the time
a load ran. The exit air is warmer than the entrance air. *Without
knowing the
volume of air my dryer blows, I can't tell if that adds much to the
cost.

I think the Kill-a-Watt EZ will do all that. *I believe it measures
instantaneous wattage AND accumulates kWhrs.... *about $25 at Costco.
I have one, but haven't used it yet.

You have a 110 V dryer?

Heh.... *good point....
I wonder if you could use two Kill-a-Watts, on different 120 V legs.... *
I might try that, cuz I bought one for my BIL.

Yeah but isn't the 220 draw from hot to hot with the only current
returning through the neutral being the 110v leg that typically runs the
light and the motor. So, I'm not sure that hooking up two of them would
work (plus I'm pretty sure they are not rated at the 35A or so amperage
of a dryer).

I think the easiest thing would be to put a clamp-on ammeter on it --
which shouldn't be too hard since one typically has easy access to the
dryer end of the cord where the wires terminate. Don't forget to measure
current in both legs of course.

Actually, with a clamp-on meter, would you get an accurate rating of
220v current if you clamped around both hot legs but with the direction
of the wire in one of the legs reversed 180 degrees -- my thinking is
that reversing the wire direction would make both currents appear in
phase and hence be additive...- Hide quoted text -

- Show quoted text -

IMO I think you would be measuring it twice.
the current flows from one end of the 220 volt supply, thorugh the the
machine, mainly the heaters, and back through the other 220 volt as a
return. Some dryers do have some 110 volt that would unbalnce that a
bit but not much.