Maker Pro
Maker Pro

Fan Power Consumption

J

Joe

Jan 1, 1970
0
I have a Lasko Premium 20" three-speed box fan. I'd like to know how many
watts it uses, but so far I can't find any good info.

No wattage info on the box or the fan, no wattage info on the Lasko website.

Googling gets me wildly disparate numbers on wattage for "portable" fans.

Does anyone have reasonably accurate info? It would be nice to know how
many watts for each of the three speeds.

Thanks.

--- Joe
 
V

Vey

Jan 1, 1970
0
Joe said:
I have a Lasko Premium 20" three-speed box fan. I'd like to know how many
watts it uses, but so far I can't find any good info.

No wattage info on the box or the fan, no wattage info on the Lasko website.

Googling gets me wildly disparate numbers on wattage for "portable" fans.

Does anyone have reasonably accurate info? It would be nice to know how
many watts for each of the three speeds.

Thanks.

--- Joe

If you really want to know the real numbers, rather than theoretical
book numbers, which are next to useless, you can buy clamp-on amp meters
for really cheap now. Then you would need an extension cord, where you
(carefully!!) split the wires, leaving both insulated, so that one could
be clamped around. These amp meters only work if one of the wires are
clamped. If you use an extension cord, you can use it for all sorts of
things around the house to see what they use too.

I was really surprised at how cheap these amp meters have gotten to be.
They are accurate, too. I took one over to a certifying lab and they
wanted to test it for free on a lark cause they couldn't believe
anything that cheap would be worth a damn. Not many years ago, they cost
hundreds, now they are down to $20 or so from here:
 
I

ian field

Jan 1, 1970
0
Joe said:
I have a Lasko Premium 20" three-speed box fan. I'd like to know how many
watts it uses, but so far I can't find any good info.

No wattage info on the box or the fan, no wattage info on the Lasko
website.

Googling gets me wildly disparate numbers on wattage for "portable" fans.

Does anyone have reasonably accurate info? It would be nice to know how
many watts for each of the three speeds.

Thanks.

--- Joe

Put a low value resistor in the neutral lead and measure the volt drop, if
its an AC supply and the fan is an inductive load this won't be exactly
accurate - but probably close enough.
 
N

N Cook

Jan 1, 1970
0
....
I have a Lasko Premium 20" three-speed box fan. I'd like to know how many
watts it uses, but so far I can't find any good info.

No wattage info on the box or the fan, no wattage info on the Lasko website.

Googling gets me wildly disparate numbers on wattage for "portable" fans.

Does anyone have reasonably accurate info? It would be nice to know how
many watts for each of the three speeds.

Thanks.

--- Joe

With nothing much , other than clocks on in the house , take a reading on
the billing consumption meter and then 10 minutes later. Then time for 10
minutes each of the 3 settings and consequential consumption readings
 
This is the next to useless number I mentioned in my post. It is the
theoretical maximum amount based on the theoretical voltage. In the
field, voltage can vary and so can the usage. I know it sounds nutty,
but I've seen variations of more than 15% from the theory and that, to
me, is unacceptable.

If +/- 15 % is unacceptable then the clamp on ampmeter you suggested
from Harbor Freight would also be unacceptable.
 
J

John Popelish

Jan 1, 1970
0
Joe said:
I have a Lasko Premium 20" three-speed box fan. I'd like to know how many
watts it uses, but so far I can't find any good info.

No wattage info on the box or the fan, no wattage info on the Lasko website.

Googling gets me wildly disparate numbers on wattage for "portable" fans.

Does anyone have reasonably accurate info? It would be nice to know how
many watts for each of the three speeds.

For an actual measurement, you could plug it into one of
these meters:
http://www.supermediastore.com/kilw...tt&WT.srch=1&gclid=COH1ovnZr40CFSNFgQod3jdUtQ
 
V

Vey

Jan 1, 1970
0
If +/- 15 % is unacceptable then the clamp on ampmeter you suggested
from Harbor Freight would also be unacceptable.

Don't assume. Buy it and test it like I did. The lab said +-3%. I
consider that to be acceptable. If you don't like those numbers, then
buy one for $300 and compare it to what you suggest the "book" numbers are.
 
K

Ken Weitzel

Jan 1, 1970
0
Joe said:
I have a Lasko Premium 20" three-speed box fan. I'd like to know how many
watts it uses, but so far I can't find any good info.

No wattage info on the box or the fan, no wattage info on the Lasko website.

Googling gets me wildly disparate numbers on wattage for "portable" fans.

Does anyone have reasonably accurate info? It would be nice to know how
many watts for each of the three speeds.

Thanks.

--- Joe

Hi Joe...

It's going to continue to be a bit confusing... google lasko fan watts
and you'll find several entries that include comsumption.... but most
say 170 watts, one says 165 watts, and yet another 70 watts.

There must be a rating plate somewhere on the machine or motor,
though... isn't it a legal requirement?

Take care.

Ken
 
J

James Sweet

Jan 1, 1970
0
Vey said:
If you really want to know the real numbers, rather than theoretical book
numbers, which are next to useless, you can buy clamp-on amp meters for
really cheap now. Then you would need an extension cord, where you
(carefully!!) split the wires, leaving both insulated, so that one could
be clamped around. These amp meters only work if one of the wires are
clamped. If you use an extension cord, you can use it for all sorts of
things around the house to see what they use too.

I was really surprised at how cheap these amp meters have gotten to be.
They are accurate, too. I took one over to a certifying lab and they
wanted to test it for free on a lark cause they couldn't believe anything
that cheap would be worth a damn. Not many years ago, they cost hundreds,
now they are down to $20 or so from here:


There's much better solutions than that, especially for the novice.

http://www.amazon.com/P3-Internatio...3?ie=UTF8&s=electronics&qid=1184721430&sr=8-1

I have one, it does a good job of measuring voltage, amperage draw,
volt-amps, power factor, watts, and cumulative kilowatt-hours.
 
J

James Sweet

Jan 1, 1970
0
Vey said:
Don't assume. Buy it and test it like I did. The lab said +-3%. I consider
that to be acceptable. If you don't like those numbers, then buy one for
$300 and compare it to what you suggest the "book" numbers are.

You still don't know what the power factor is with that route, a lot of
cheap motors are closer to 0.5 than to unity, so the calculated wattage can
be nearly double what the motor actually draws.
 
T

The Phantom

Jan 1, 1970
0
I have a Lasko Premium 20" three-speed box fan. I'd like to know how many
watts it uses, but so far I can't find any good info.

No wattage info on the box or the fan, no wattage info on the Lasko website.

Googling gets me wildly disparate numbers on wattage for "portable" fans.

Does anyone have reasonably accurate info? It would be nice to know how
many watts for each of the three speeds.

Thanks.

--- Joe

I have an older GE 20" window fan. It only has two speeds, but here are
the measurements:

Speed True watts Amps Volts Power Factor

Low 94 1.18 121.8 .6535

High 194 2.38 121.3 .672

Power was measured with a Yokogawa analog wattmeter; applied voltage and
current with a Fluke 189.

This power factor is probably typical for an induction motor of this size.
 
I

ian field

Jan 1, 1970
0
Vey said:
This is the next to useless number I mentioned in my post. It is the
theoretical maximum amount based on the theoretical voltage. In the field,
voltage can vary and so can the usage. I know it sounds nutty, but I've
seen variations of more than 15% from the theory and that, to me, is
unacceptable.

If its a ventilation fan exposed to the great outdoors, wind direction could
easily account for a 15% variation in power draw.
 
B

Bill Jeffrey

Jan 1, 1970
0
Joe said:
I have a Lasko Premium 20" three-speed box fan. I'd like to know how many
watts it uses, but so far I can't find any good info.

No wattage info on the box or the fan, no wattage info on the Lasko website.

Googling gets me wildly disparate numbers on wattage for "portable" fans.

Does anyone have reasonably accurate info? It would be nice to know how
many watts for each of the three speeds.

Thanks.

--- Joe
I have a 20" Lasko in front of me at the moment. My Kill-A-Watt says

99/136/196 watts
129/175/248 volt-amps
at 121 volts

And no, there is no electrical info plate or marking on any of several
of these cheapie box fans that I own.

Bill Jeffrey
 
J

Joe

Jan 1, 1970
0
Bill Jeffrey said:
I have a 20" Lasko in front of me at the moment. My Kill-A-Watt says

99/136/196 watts
129/175/248 volt-amps
at 121 volts

And no, there is no electrical info plate or marking on any of several
of these cheapie box fans that I own.

Bill Jeffrey

Thanks a lot, Bill. Is your Lasko a model 3723? That's the one I have
(two of, actually).

Also, I went to the Kill-A-Watt web site. It looks like you can't measure
any appliance running at 220 volts, correct?

I have a wall A/C unit in my apartment that plugs into a 220 outlet. I
read somewhere that even a fairly small one of these units uses 3500
watts. I imagine that the 3500 is only when the A/C is running the
compressor. So the average wattage would depend greatly on the outside
temperature, I would think.

--- Joe
 
J

James Sweet

Jan 1, 1970
0
Also, I went to the Kill-A-Watt web site. It looks like you can't measure
any appliance running at 220 volts, correct?

I have a wall A/C unit in my apartment that plugs into a 220 outlet. I
read somewhere that even a fairly small one of these units uses 3500
watts. I imagine that the 3500 is only when the A/C is running the
compressor. So the average wattage would depend greatly on the outside
temperature, I would think.


I have the UK version which is not even branded, but looking at it, it's
obviously internally identical to the Kill-A-Watt. It's designed for 240V
but works fine all the way down to 60V so I suspect the 120V model will work
on 240V but have not opened one up to compare. At any rate the power supply
is a simple capacitor and zener arrangement so it would be easy enough to
modify with a lower value capacitor if the zener heats up too much on 240.
If in doubt, it shouldn't be too hard to get the UK model and build some
plug adapters as I did, back before it was widely available in the US.

I used mine to measure the draw of my 3 ton (36,000 BTU) central AC and
found that the outdoor unit draws about 3500W with a power factor of 0.91.
You're correct that current draw varies with head pressure which varies with
outdoor ambient temperature. I doubt your window AC is bigger than 1 ton, so
even with the indoor fan, I'd be shocked to see it drawing more than 2KW and
really it's probably closer to 1200W.
 
B

Bill Jeffrey

Jan 1, 1970
0
Joe said:
Thanks a lot, Bill. Is your Lasko a model 3723? That's the one I have
(two of, actually).

Also, I went to the Kill-A-Watt web site. It looks like you can't measure
any appliance running at 220 volts, correct?

I have a wall A/C unit in my apartment that plugs into a 220 outlet. I
read somewhere that even a fairly small one of these units uses 3500
watts. I imagine that the 3500 is only when the A/C is running the
compressor. So the average wattage would depend greatly on the outside
temperature, I would think.

--- Joe

Hey, I found the "electrical info plate" on the Lasko. It was stamped
into the sheet metal on the bottom of the fan. After being stamped, the
sheet metal was painted, which obscured the stamped info so completely
that the only way I can see it only with a bright light held at an
angle. As near as I can tell, it says
"Model 3723 (last two digits very unclear, could be almost anything)
Style EC437 (again very unclear)
Type 1
E20739
Listed 154C (UL symbol)
120v 2.2amp 60hz
1922.91"

Bill
 
E

Esther & Fester Bestertester

Jan 1, 1970
0
Having some issues with the landlord over your utility charges?

FBt
 
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