Why do the vast majority of variable speed fans start out on high?
Just about every fan I've used that has 3 speeds - window, ceiling, floor,
etc. - all go from Off to High to Medium to Slow.
The other day I had the chance to use a fan with a infinitely variable knob
and it too started on high and slowed down as the knob was turned.
As far as I know, only my vehicle fans start slow and get faster as the
control is turned.
It is easier to build the electronics that way or do manufacturers just
assume that we all will use our fans on high most of the time, except in
House hold fans come from a time when they were very inefficient and tended
to overheat if started on low. (some would not start at all and if that
happened could cause a fire) BTW heater fans in the older cars had the same
Most 120VAC fans out there have shaded pole or PSC motors that are low
starting torque motors. At the same time, the motors cannot get stalled
lest they begin to draw high current and overheat. So, the designers might
want to increase the chances of the fan starting normally by throwing it
into HIGH first. In this motors high means "high torque", not "high speed"
per se. So, HIGH will give it more torque to overcome the staring
friction, the inertia and all that hair that found its way onto the
By the way, not all of them start with high first but you're right, many
do. My own fans turned out to be 50/50 in terms of speed out of OFF.
In terms of electronics. it's exactly the same as far as building it but
I, too, run my fans on high most of the time. If I didn't need it as
powerful, I would have probably bought a smaller model instead.
Every fan I use starts out slower when first turned on, but as it heats up
goes faster. I'm fully aware of that fact, are others ? Besides, if went to
turn off a fan, you might miss off and use low, and not know it.
such a fan 'needs' to start fast, so while you're there turning on the
fan, you might as well adjust it to slower - very clever system
design, requiring the Operator to slow it down.
Or, when turning it OFF there is no possibility of error, good point.
No one mentioned the wear and tear on the switch. The german radio/
audio amplifier mfgrs started setting the analog maximum volume at the
OFF position so the wear of low volume didn't happen to your switch.
Ok turning ON, but a real nuisance when turning OFF - had to wait for
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