Fan speed switch: why OFF :: HIGH :: MED :: LOW?











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Many AC fans, including inexpensive floor models, have a rotary speed control which rotates from OFF to HIGH to MED to LOW. Since the switch does not rotate 360°, you have to rotate it backwards to shut it off. This has always slightly annoyed me, because it appears to make no logical sense to have to speed the fan up to turn it off.



Why are the speed settings from fastest to slowest? This design seems counter-intuitive, but I assume there is a good reason because the design is so common.










share|improve this question




















  • 4




    Just to note, ceiling fans with a pull cord seem to follow the paradigm too, only it cycles from low to off and then back to high again.
    – Michael
    Nov 3 at 17:18










  • @Michael Ceiling fans with a rotary switch though often have a circular option. Go from 0 > 1 > 2 > 3 > 4 > 5 > 0. But those take a lot longer to accelerate to the set speed than small floor models, so they have a different design altogether.
    – Mast
    Nov 4 at 13:22








  • 1




    I have five ceiling fans at home and one of them is opposite this - it goes off to low to medium to high - and it drives everyone crazy. Whether there is currently a reason for the common design or not, there is certainly a precedent created by fans having this design that makes it logical to keep it that way.
    – Moshe Katz
    Nov 4 at 23:30








  • 1




    @MosheKatz I've seen a few floor fans now that use the more intuitive off-low-med-high which indeed is simultaneously counterintuitive if you have done it the other way your whole life. It may be that there is a switchover to Brushless DC motors in some models, which have embedded electronics that knows how to start the motor, and for which the low-med-high fan speed settings are really just targets for the circuit to achieve.
    – uhoh
    2 days ago

















up vote
52
down vote

favorite
7












Many AC fans, including inexpensive floor models, have a rotary speed control which rotates from OFF to HIGH to MED to LOW. Since the switch does not rotate 360°, you have to rotate it backwards to shut it off. This has always slightly annoyed me, because it appears to make no logical sense to have to speed the fan up to turn it off.



Why are the speed settings from fastest to slowest? This design seems counter-intuitive, but I assume there is a good reason because the design is so common.










share|improve this question




















  • 4




    Just to note, ceiling fans with a pull cord seem to follow the paradigm too, only it cycles from low to off and then back to high again.
    – Michael
    Nov 3 at 17:18










  • @Michael Ceiling fans with a rotary switch though often have a circular option. Go from 0 > 1 > 2 > 3 > 4 > 5 > 0. But those take a lot longer to accelerate to the set speed than small floor models, so they have a different design altogether.
    – Mast
    Nov 4 at 13:22








  • 1




    I have five ceiling fans at home and one of them is opposite this - it goes off to low to medium to high - and it drives everyone crazy. Whether there is currently a reason for the common design or not, there is certainly a precedent created by fans having this design that makes it logical to keep it that way.
    – Moshe Katz
    Nov 4 at 23:30








  • 1




    @MosheKatz I've seen a few floor fans now that use the more intuitive off-low-med-high which indeed is simultaneously counterintuitive if you have done it the other way your whole life. It may be that there is a switchover to Brushless DC motors in some models, which have embedded electronics that knows how to start the motor, and for which the low-med-high fan speed settings are really just targets for the circuit to achieve.
    – uhoh
    2 days ago















up vote
52
down vote

favorite
7









up vote
52
down vote

favorite
7






7





Many AC fans, including inexpensive floor models, have a rotary speed control which rotates from OFF to HIGH to MED to LOW. Since the switch does not rotate 360°, you have to rotate it backwards to shut it off. This has always slightly annoyed me, because it appears to make no logical sense to have to speed the fan up to turn it off.



Why are the speed settings from fastest to slowest? This design seems counter-intuitive, but I assume there is a good reason because the design is so common.










share|improve this question















Many AC fans, including inexpensive floor models, have a rotary speed control which rotates from OFF to HIGH to MED to LOW. Since the switch does not rotate 360°, you have to rotate it backwards to shut it off. This has always slightly annoyed me, because it appears to make no logical sense to have to speed the fan up to turn it off.



Why are the speed settings from fastest to slowest? This design seems counter-intuitive, but I assume there is a good reason because the design is so common.







motor switches induction-motor fan






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Nov 3 at 17:40

























asked Nov 3 at 12:23









RichF

538510




538510








  • 4




    Just to note, ceiling fans with a pull cord seem to follow the paradigm too, only it cycles from low to off and then back to high again.
    – Michael
    Nov 3 at 17:18










  • @Michael Ceiling fans with a rotary switch though often have a circular option. Go from 0 > 1 > 2 > 3 > 4 > 5 > 0. But those take a lot longer to accelerate to the set speed than small floor models, so they have a different design altogether.
    – Mast
    Nov 4 at 13:22








  • 1




    I have five ceiling fans at home and one of them is opposite this - it goes off to low to medium to high - and it drives everyone crazy. Whether there is currently a reason for the common design or not, there is certainly a precedent created by fans having this design that makes it logical to keep it that way.
    – Moshe Katz
    Nov 4 at 23:30








  • 1




    @MosheKatz I've seen a few floor fans now that use the more intuitive off-low-med-high which indeed is simultaneously counterintuitive if you have done it the other way your whole life. It may be that there is a switchover to Brushless DC motors in some models, which have embedded electronics that knows how to start the motor, and for which the low-med-high fan speed settings are really just targets for the circuit to achieve.
    – uhoh
    2 days ago
















  • 4




    Just to note, ceiling fans with a pull cord seem to follow the paradigm too, only it cycles from low to off and then back to high again.
    – Michael
    Nov 3 at 17:18










  • @Michael Ceiling fans with a rotary switch though often have a circular option. Go from 0 > 1 > 2 > 3 > 4 > 5 > 0. But those take a lot longer to accelerate to the set speed than small floor models, so they have a different design altogether.
    – Mast
    Nov 4 at 13:22








  • 1




    I have five ceiling fans at home and one of them is opposite this - it goes off to low to medium to high - and it drives everyone crazy. Whether there is currently a reason for the common design or not, there is certainly a precedent created by fans having this design that makes it logical to keep it that way.
    – Moshe Katz
    Nov 4 at 23:30








  • 1




    @MosheKatz I've seen a few floor fans now that use the more intuitive off-low-med-high which indeed is simultaneously counterintuitive if you have done it the other way your whole life. It may be that there is a switchover to Brushless DC motors in some models, which have embedded electronics that knows how to start the motor, and for which the low-med-high fan speed settings are really just targets for the circuit to achieve.
    – uhoh
    2 days ago










4




4




Just to note, ceiling fans with a pull cord seem to follow the paradigm too, only it cycles from low to off and then back to high again.
– Michael
Nov 3 at 17:18




Just to note, ceiling fans with a pull cord seem to follow the paradigm too, only it cycles from low to off and then back to high again.
– Michael
Nov 3 at 17:18












@Michael Ceiling fans with a rotary switch though often have a circular option. Go from 0 > 1 > 2 > 3 > 4 > 5 > 0. But those take a lot longer to accelerate to the set speed than small floor models, so they have a different design altogether.
– Mast
Nov 4 at 13:22






@Michael Ceiling fans with a rotary switch though often have a circular option. Go from 0 > 1 > 2 > 3 > 4 > 5 > 0. But those take a lot longer to accelerate to the set speed than small floor models, so they have a different design altogether.
– Mast
Nov 4 at 13:22






1




1




I have five ceiling fans at home and one of them is opposite this - it goes off to low to medium to high - and it drives everyone crazy. Whether there is currently a reason for the common design or not, there is certainly a precedent created by fans having this design that makes it logical to keep it that way.
– Moshe Katz
Nov 4 at 23:30






I have five ceiling fans at home and one of them is opposite this - it goes off to low to medium to high - and it drives everyone crazy. Whether there is currently a reason for the common design or not, there is certainly a precedent created by fans having this design that makes it logical to keep it that way.
– Moshe Katz
Nov 4 at 23:30






1




1




@MosheKatz I've seen a few floor fans now that use the more intuitive off-low-med-high which indeed is simultaneously counterintuitive if you have done it the other way your whole life. It may be that there is a switchover to Brushless DC motors in some models, which have embedded electronics that knows how to start the motor, and for which the low-med-high fan speed settings are really just targets for the circuit to achieve.
– uhoh
2 days ago






@MosheKatz I've seen a few floor fans now that use the more intuitive off-low-med-high which indeed is simultaneously counterintuitive if you have done it the other way your whole life. It may be that there is a switchover to Brushless DC motors in some models, which have embedded electronics that knows how to start the motor, and for which the low-med-high fan speed settings are really just targets for the circuit to achieve.
– uhoh
2 days ago












3 Answers
3






active

oldest

votes

















up vote
84
down vote



accepted










Fans of that type have induction motors with two windings with a capacitor in series with one of the windings. For every individual motor design there is a certain capacitor value that allows the motor to develop maximum torque and operate at the maximum corresponding speed. Smaller capacitor values are used to reduce the torque so that the load overcomes the motor's torque and slows the motor down.



When the motor is turned on, the motor must overcome the static friction of the bearings and get the fan moving. It must then accelerate the motor inertia. That means that using the highest torque setting is desirable for starting the motor. Once the fan is moving, the torque can be reduced for lower speed operation.






share|improve this answer



















  • 4




    Starting on high is also preferred for non-induction motors, when the application allows.
    – Brock Adams
    Nov 3 at 17:43






  • 4




    Seems like this could be tested by unplugging the fan, turning the switch to low, and plugging the fan back in, couldn’t it?
    – dudeman
    Nov 4 at 4:55






  • 10




    @dudeman I have a cheap fan blowing on me at this very moment where I have to turn it to high for a few seconds before switching to low or else it never gets enough speed to keep spinning.
    – fluffy
    Nov 4 at 5:04






  • 4




    So it's effectively an abstraction leak, albeit a fair one for a simple mechanical process.
    – Lightness Races in Orbit
    2 days ago






  • 1




    I have several cheap box fans throughout my house, all with High as the first setting, and all perfectly able to start on the Low setting. Static friction certainly doesn't seem to be a concern here. Maybe they're designing for 10 years from now when the motor is filled with dust, but I'd like to see confirmation of this from one of the actual designers.
    – James
    2 days ago


















up vote
12
down vote













It may be intentionally designed to force the fan on "high" for it to spin up before allowing it to drop back down to "low"



The amount of power needed to overcome the static rolling resistance can be higher than what is output to maintain the "low" speed, thus it could end up stalling and not moving or only wiggling back and forth on a "low" setting






share|improve this answer




























    up vote
    7
    down vote













    Not just fans



    A lot of devices are designed this way. It almost seems standard, even though I agree it is counter-intuitive.



    For example, in my kitchen I have:




    • Cooktop hood fan/light - fan goes from Off to High to Low (continuous except for switch Off)

    • Cooktop hood fan/light - light goes from Off to High to Low (discrete settings)

    • Cooktop gas burners - Off to High to Low (continuous except for switch Off)


    In the case of the fan, the other answers regarding motor startup make sense and would apply to this fan as well.



    In the case of the light, I suspect it is to match the fan since it is part of the same device.



    In the case of the burners, I think it is because ignition needs to be done when first turning on a burner and ignition is most reliable on the High setting, so starting with High makes sense.



    The end result is all using the counter-intuitive Off->High->Low






    share|improve this answer

















    • 3




      The gas burners are because ignition is more reliable at high power (conceptually similar to the fans), and the flame-out sensor needs a bit of warming up, which can take a long time on low. My cooker hood extractor has discrete settings and can be left on low with a separate on switch - just as well as high is deafening
      – Chris H
      2 days ago






    • 6




      The gas burner settings are made so that you can't accidentally turn the cooker off when trying to achieve a low setting. The difference between just-on and just-off is harder to distinguish than full-on and full-off. I would not be surprised if the same reasoning applies to fans.
      – Sanchises
      2 days ago










    • My cooktop hood fan has four separate buttons for off, low, medium, high and you can start it by pressing any one of the three "not-off" buttons.
      – David Richerby
      2 days ago











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    3 Answers
    3






    active

    oldest

    votes








    3 Answers
    3






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes








    up vote
    84
    down vote



    accepted










    Fans of that type have induction motors with two windings with a capacitor in series with one of the windings. For every individual motor design there is a certain capacitor value that allows the motor to develop maximum torque and operate at the maximum corresponding speed. Smaller capacitor values are used to reduce the torque so that the load overcomes the motor's torque and slows the motor down.



    When the motor is turned on, the motor must overcome the static friction of the bearings and get the fan moving. It must then accelerate the motor inertia. That means that using the highest torque setting is desirable for starting the motor. Once the fan is moving, the torque can be reduced for lower speed operation.






    share|improve this answer



















    • 4




      Starting on high is also preferred for non-induction motors, when the application allows.
      – Brock Adams
      Nov 3 at 17:43






    • 4




      Seems like this could be tested by unplugging the fan, turning the switch to low, and plugging the fan back in, couldn’t it?
      – dudeman
      Nov 4 at 4:55






    • 10




      @dudeman I have a cheap fan blowing on me at this very moment where I have to turn it to high for a few seconds before switching to low or else it never gets enough speed to keep spinning.
      – fluffy
      Nov 4 at 5:04






    • 4




      So it's effectively an abstraction leak, albeit a fair one for a simple mechanical process.
      – Lightness Races in Orbit
      2 days ago






    • 1




      I have several cheap box fans throughout my house, all with High as the first setting, and all perfectly able to start on the Low setting. Static friction certainly doesn't seem to be a concern here. Maybe they're designing for 10 years from now when the motor is filled with dust, but I'd like to see confirmation of this from one of the actual designers.
      – James
      2 days ago















    up vote
    84
    down vote



    accepted










    Fans of that type have induction motors with two windings with a capacitor in series with one of the windings. For every individual motor design there is a certain capacitor value that allows the motor to develop maximum torque and operate at the maximum corresponding speed. Smaller capacitor values are used to reduce the torque so that the load overcomes the motor's torque and slows the motor down.



    When the motor is turned on, the motor must overcome the static friction of the bearings and get the fan moving. It must then accelerate the motor inertia. That means that using the highest torque setting is desirable for starting the motor. Once the fan is moving, the torque can be reduced for lower speed operation.






    share|improve this answer



















    • 4




      Starting on high is also preferred for non-induction motors, when the application allows.
      – Brock Adams
      Nov 3 at 17:43






    • 4




      Seems like this could be tested by unplugging the fan, turning the switch to low, and plugging the fan back in, couldn’t it?
      – dudeman
      Nov 4 at 4:55






    • 10




      @dudeman I have a cheap fan blowing on me at this very moment where I have to turn it to high for a few seconds before switching to low or else it never gets enough speed to keep spinning.
      – fluffy
      Nov 4 at 5:04






    • 4




      So it's effectively an abstraction leak, albeit a fair one for a simple mechanical process.
      – Lightness Races in Orbit
      2 days ago






    • 1




      I have several cheap box fans throughout my house, all with High as the first setting, and all perfectly able to start on the Low setting. Static friction certainly doesn't seem to be a concern here. Maybe they're designing for 10 years from now when the motor is filled with dust, but I'd like to see confirmation of this from one of the actual designers.
      – James
      2 days ago













    up vote
    84
    down vote



    accepted







    up vote
    84
    down vote



    accepted






    Fans of that type have induction motors with two windings with a capacitor in series with one of the windings. For every individual motor design there is a certain capacitor value that allows the motor to develop maximum torque and operate at the maximum corresponding speed. Smaller capacitor values are used to reduce the torque so that the load overcomes the motor's torque and slows the motor down.



    When the motor is turned on, the motor must overcome the static friction of the bearings and get the fan moving. It must then accelerate the motor inertia. That means that using the highest torque setting is desirable for starting the motor. Once the fan is moving, the torque can be reduced for lower speed operation.






    share|improve this answer














    Fans of that type have induction motors with two windings with a capacitor in series with one of the windings. For every individual motor design there is a certain capacitor value that allows the motor to develop maximum torque and operate at the maximum corresponding speed. Smaller capacitor values are used to reduce the torque so that the load overcomes the motor's torque and slows the motor down.



    When the motor is turned on, the motor must overcome the static friction of the bearings and get the fan moving. It must then accelerate the motor inertia. That means that using the highest torque setting is desirable for starting the motor. Once the fan is moving, the torque can be reduced for lower speed operation.







    share|improve this answer














    share|improve this answer



    share|improve this answer








    edited 2 days ago

























    answered Nov 3 at 13:24









    Charles Cowie

    19.3k11537




    19.3k11537








    • 4




      Starting on high is also preferred for non-induction motors, when the application allows.
      – Brock Adams
      Nov 3 at 17:43






    • 4




      Seems like this could be tested by unplugging the fan, turning the switch to low, and plugging the fan back in, couldn’t it?
      – dudeman
      Nov 4 at 4:55






    • 10




      @dudeman I have a cheap fan blowing on me at this very moment where I have to turn it to high for a few seconds before switching to low or else it never gets enough speed to keep spinning.
      – fluffy
      Nov 4 at 5:04






    • 4




      So it's effectively an abstraction leak, albeit a fair one for a simple mechanical process.
      – Lightness Races in Orbit
      2 days ago






    • 1




      I have several cheap box fans throughout my house, all with High as the first setting, and all perfectly able to start on the Low setting. Static friction certainly doesn't seem to be a concern here. Maybe they're designing for 10 years from now when the motor is filled with dust, but I'd like to see confirmation of this from one of the actual designers.
      – James
      2 days ago














    • 4




      Starting on high is also preferred for non-induction motors, when the application allows.
      – Brock Adams
      Nov 3 at 17:43






    • 4




      Seems like this could be tested by unplugging the fan, turning the switch to low, and plugging the fan back in, couldn’t it?
      – dudeman
      Nov 4 at 4:55






    • 10




      @dudeman I have a cheap fan blowing on me at this very moment where I have to turn it to high for a few seconds before switching to low or else it never gets enough speed to keep spinning.
      – fluffy
      Nov 4 at 5:04






    • 4




      So it's effectively an abstraction leak, albeit a fair one for a simple mechanical process.
      – Lightness Races in Orbit
      2 days ago






    • 1




      I have several cheap box fans throughout my house, all with High as the first setting, and all perfectly able to start on the Low setting. Static friction certainly doesn't seem to be a concern here. Maybe they're designing for 10 years from now when the motor is filled with dust, but I'd like to see confirmation of this from one of the actual designers.
      – James
      2 days ago








    4




    4




    Starting on high is also preferred for non-induction motors, when the application allows.
    – Brock Adams
    Nov 3 at 17:43




    Starting on high is also preferred for non-induction motors, when the application allows.
    – Brock Adams
    Nov 3 at 17:43




    4




    4




    Seems like this could be tested by unplugging the fan, turning the switch to low, and plugging the fan back in, couldn’t it?
    – dudeman
    Nov 4 at 4:55




    Seems like this could be tested by unplugging the fan, turning the switch to low, and plugging the fan back in, couldn’t it?
    – dudeman
    Nov 4 at 4:55




    10




    10




    @dudeman I have a cheap fan blowing on me at this very moment where I have to turn it to high for a few seconds before switching to low or else it never gets enough speed to keep spinning.
    – fluffy
    Nov 4 at 5:04




    @dudeman I have a cheap fan blowing on me at this very moment where I have to turn it to high for a few seconds before switching to low or else it never gets enough speed to keep spinning.
    – fluffy
    Nov 4 at 5:04




    4




    4




    So it's effectively an abstraction leak, albeit a fair one for a simple mechanical process.
    – Lightness Races in Orbit
    2 days ago




    So it's effectively an abstraction leak, albeit a fair one for a simple mechanical process.
    – Lightness Races in Orbit
    2 days ago




    1




    1




    I have several cheap box fans throughout my house, all with High as the first setting, and all perfectly able to start on the Low setting. Static friction certainly doesn't seem to be a concern here. Maybe they're designing for 10 years from now when the motor is filled with dust, but I'd like to see confirmation of this from one of the actual designers.
    – James
    2 days ago




    I have several cheap box fans throughout my house, all with High as the first setting, and all perfectly able to start on the Low setting. Static friction certainly doesn't seem to be a concern here. Maybe they're designing for 10 years from now when the motor is filled with dust, but I'd like to see confirmation of this from one of the actual designers.
    – James
    2 days ago












    up vote
    12
    down vote













    It may be intentionally designed to force the fan on "high" for it to spin up before allowing it to drop back down to "low"



    The amount of power needed to overcome the static rolling resistance can be higher than what is output to maintain the "low" speed, thus it could end up stalling and not moving or only wiggling back and forth on a "low" setting






    share|improve this answer

























      up vote
      12
      down vote













      It may be intentionally designed to force the fan on "high" for it to spin up before allowing it to drop back down to "low"



      The amount of power needed to overcome the static rolling resistance can be higher than what is output to maintain the "low" speed, thus it could end up stalling and not moving or only wiggling back and forth on a "low" setting






      share|improve this answer























        up vote
        12
        down vote










        up vote
        12
        down vote









        It may be intentionally designed to force the fan on "high" for it to spin up before allowing it to drop back down to "low"



        The amount of power needed to overcome the static rolling resistance can be higher than what is output to maintain the "low" speed, thus it could end up stalling and not moving or only wiggling back and forth on a "low" setting






        share|improve this answer












        It may be intentionally designed to force the fan on "high" for it to spin up before allowing it to drop back down to "low"



        The amount of power needed to overcome the static rolling resistance can be higher than what is output to maintain the "low" speed, thus it could end up stalling and not moving or only wiggling back and forth on a "low" setting







        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered Nov 3 at 17:44









        user2813274

        362220




        362220






















            up vote
            7
            down vote













            Not just fans



            A lot of devices are designed this way. It almost seems standard, even though I agree it is counter-intuitive.



            For example, in my kitchen I have:




            • Cooktop hood fan/light - fan goes from Off to High to Low (continuous except for switch Off)

            • Cooktop hood fan/light - light goes from Off to High to Low (discrete settings)

            • Cooktop gas burners - Off to High to Low (continuous except for switch Off)


            In the case of the fan, the other answers regarding motor startup make sense and would apply to this fan as well.



            In the case of the light, I suspect it is to match the fan since it is part of the same device.



            In the case of the burners, I think it is because ignition needs to be done when first turning on a burner and ignition is most reliable on the High setting, so starting with High makes sense.



            The end result is all using the counter-intuitive Off->High->Low






            share|improve this answer

















            • 3




              The gas burners are because ignition is more reliable at high power (conceptually similar to the fans), and the flame-out sensor needs a bit of warming up, which can take a long time on low. My cooker hood extractor has discrete settings and can be left on low with a separate on switch - just as well as high is deafening
              – Chris H
              2 days ago






            • 6




              The gas burner settings are made so that you can't accidentally turn the cooker off when trying to achieve a low setting. The difference between just-on and just-off is harder to distinguish than full-on and full-off. I would not be surprised if the same reasoning applies to fans.
              – Sanchises
              2 days ago










            • My cooktop hood fan has four separate buttons for off, low, medium, high and you can start it by pressing any one of the three "not-off" buttons.
              – David Richerby
              2 days ago















            up vote
            7
            down vote













            Not just fans



            A lot of devices are designed this way. It almost seems standard, even though I agree it is counter-intuitive.



            For example, in my kitchen I have:




            • Cooktop hood fan/light - fan goes from Off to High to Low (continuous except for switch Off)

            • Cooktop hood fan/light - light goes from Off to High to Low (discrete settings)

            • Cooktop gas burners - Off to High to Low (continuous except for switch Off)


            In the case of the fan, the other answers regarding motor startup make sense and would apply to this fan as well.



            In the case of the light, I suspect it is to match the fan since it is part of the same device.



            In the case of the burners, I think it is because ignition needs to be done when first turning on a burner and ignition is most reliable on the High setting, so starting with High makes sense.



            The end result is all using the counter-intuitive Off->High->Low






            share|improve this answer

















            • 3




              The gas burners are because ignition is more reliable at high power (conceptually similar to the fans), and the flame-out sensor needs a bit of warming up, which can take a long time on low. My cooker hood extractor has discrete settings and can be left on low with a separate on switch - just as well as high is deafening
              – Chris H
              2 days ago






            • 6




              The gas burner settings are made so that you can't accidentally turn the cooker off when trying to achieve a low setting. The difference between just-on and just-off is harder to distinguish than full-on and full-off. I would not be surprised if the same reasoning applies to fans.
              – Sanchises
              2 days ago










            • My cooktop hood fan has four separate buttons for off, low, medium, high and you can start it by pressing any one of the three "not-off" buttons.
              – David Richerby
              2 days ago













            up vote
            7
            down vote










            up vote
            7
            down vote









            Not just fans



            A lot of devices are designed this way. It almost seems standard, even though I agree it is counter-intuitive.



            For example, in my kitchen I have:




            • Cooktop hood fan/light - fan goes from Off to High to Low (continuous except for switch Off)

            • Cooktop hood fan/light - light goes from Off to High to Low (discrete settings)

            • Cooktop gas burners - Off to High to Low (continuous except for switch Off)


            In the case of the fan, the other answers regarding motor startup make sense and would apply to this fan as well.



            In the case of the light, I suspect it is to match the fan since it is part of the same device.



            In the case of the burners, I think it is because ignition needs to be done when first turning on a burner and ignition is most reliable on the High setting, so starting with High makes sense.



            The end result is all using the counter-intuitive Off->High->Low






            share|improve this answer












            Not just fans



            A lot of devices are designed this way. It almost seems standard, even though I agree it is counter-intuitive.



            For example, in my kitchen I have:




            • Cooktop hood fan/light - fan goes from Off to High to Low (continuous except for switch Off)

            • Cooktop hood fan/light - light goes from Off to High to Low (discrete settings)

            • Cooktop gas burners - Off to High to Low (continuous except for switch Off)


            In the case of the fan, the other answers regarding motor startup make sense and would apply to this fan as well.



            In the case of the light, I suspect it is to match the fan since it is part of the same device.



            In the case of the burners, I think it is because ignition needs to be done when first turning on a burner and ignition is most reliable on the High setting, so starting with High makes sense.



            The end result is all using the counter-intuitive Off->High->Low







            share|improve this answer












            share|improve this answer



            share|improve this answer










            answered Nov 4 at 2:12









            manassehkatz

            20516




            20516








            • 3




              The gas burners are because ignition is more reliable at high power (conceptually similar to the fans), and the flame-out sensor needs a bit of warming up, which can take a long time on low. My cooker hood extractor has discrete settings and can be left on low with a separate on switch - just as well as high is deafening
              – Chris H
              2 days ago






            • 6




              The gas burner settings are made so that you can't accidentally turn the cooker off when trying to achieve a low setting. The difference between just-on and just-off is harder to distinguish than full-on and full-off. I would not be surprised if the same reasoning applies to fans.
              – Sanchises
              2 days ago










            • My cooktop hood fan has four separate buttons for off, low, medium, high and you can start it by pressing any one of the three "not-off" buttons.
              – David Richerby
              2 days ago














            • 3




              The gas burners are because ignition is more reliable at high power (conceptually similar to the fans), and the flame-out sensor needs a bit of warming up, which can take a long time on low. My cooker hood extractor has discrete settings and can be left on low with a separate on switch - just as well as high is deafening
              – Chris H
              2 days ago






            • 6




              The gas burner settings are made so that you can't accidentally turn the cooker off when trying to achieve a low setting. The difference between just-on and just-off is harder to distinguish than full-on and full-off. I would not be surprised if the same reasoning applies to fans.
              – Sanchises
              2 days ago










            • My cooktop hood fan has four separate buttons for off, low, medium, high and you can start it by pressing any one of the three "not-off" buttons.
              – David Richerby
              2 days ago








            3




            3




            The gas burners are because ignition is more reliable at high power (conceptually similar to the fans), and the flame-out sensor needs a bit of warming up, which can take a long time on low. My cooker hood extractor has discrete settings and can be left on low with a separate on switch - just as well as high is deafening
            – Chris H
            2 days ago




            The gas burners are because ignition is more reliable at high power (conceptually similar to the fans), and the flame-out sensor needs a bit of warming up, which can take a long time on low. My cooker hood extractor has discrete settings and can be left on low with a separate on switch - just as well as high is deafening
            – Chris H
            2 days ago




            6




            6




            The gas burner settings are made so that you can't accidentally turn the cooker off when trying to achieve a low setting. The difference between just-on and just-off is harder to distinguish than full-on and full-off. I would not be surprised if the same reasoning applies to fans.
            – Sanchises
            2 days ago




            The gas burner settings are made so that you can't accidentally turn the cooker off when trying to achieve a low setting. The difference between just-on and just-off is harder to distinguish than full-on and full-off. I would not be surprised if the same reasoning applies to fans.
            – Sanchises
            2 days ago












            My cooktop hood fan has four separate buttons for off, low, medium, high and you can start it by pressing any one of the three "not-off" buttons.
            – David Richerby
            2 days ago




            My cooktop hood fan has four separate buttons for off, low, medium, high and you can start it by pressing any one of the three "not-off" buttons.
            – David Richerby
            2 days ago


















             

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