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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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ceiling fan buzzing
We have a ceiling fan in our bedroom that we sometimes like to run at
very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny |
#2
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ceiling fan buzzing
On 16 jul, 09:27, klem kedidelhopper
wrote: We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny A 120vac ceiling fan motor uses a pancake induction motor which can't be used with DC. I have seen wall rehostats for sale at hardware stores to be used with ceiling fans. Some of them have two controls, one for the ceiling fan lamp light and another for the fan. These can be installed inside a 2x4 box. The ones I have seen are manufactured by Ace Hardware. Good luck! |
#3
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ceiling fan buzzing
Are you sure it's the speed controller that's causing the problem.
I wonder if you ran it at full speed without the blades and the 'whoosh' they cause you might still hear the buzz/hum. Perhaps as an experiment power it off a resistor for a couple of seconds. On 7/16/2011 6:27 AM, klem kedidelhopper wrote: We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny |
#4
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ceiling fan buzzing
klem kedidelhopper wrote: We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny Is the speed controler made for induction motors? -- It's easy to think outside the box, when you have a cutting torch. |
#5
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ceiling fan buzzing
On Jul 16, 7:35*pm, "Michael A. Terrell"
wrote: klem kedidelhopper wrote: We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny * *Is the speed controler made for induction motors? -- It's easy to think outside the box, when you have a cutting torch. How would a speed controller made for induction motors differ from say an ordinary lamp dimmer? |
#6
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ceiling fan buzzing
klem kedidelhopper wrote: On Jul 16, 7:35 pm, "Michael A. Terrell" wrote: klem kedidelhopper wrote: We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny Is the speed controler made for induction motors? How would a speed controller made for induction motors differ from say an ordinary lamp dimmer? Lamp dimmers are simple phase controllers. They aren't designed for inductive loads. That's why most light dimmers can't be used on Florescent lights. They can cause the motor to overheat at some speeds, and cause it to be noisy or erratic at low speeds. Leviton makes variable speed fan controls with a slider to set the speed. You can get them at HD, Lowes or a lot of other building supply stores. http://www.leviton.com/OA_HTML/ibeCCtpSctDspRte.jsp?section=10857&minisite=10025 http://www.lowes.com/SearchCatalogDisplay?Ntt=speed+control&langId=-1&storeId=10151&catalogId=10051&N=0 http://www.homedepot.com/webapp/wcs/stores/servlet/Search?keyword=speed+control&selectedCatgry=SEARCH +ALL&langId=-1&storeId=10051&catalogId=10053 -- It's easy to think outside the box, when you have a cutting torch. |
#7
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ceiling fan buzzing
On Jul 17, 6:30*am, "Michael A. Terrell"
wrote: klem kedidelhopper wrote: On Jul 16, 7:35 pm, "Michael A. Terrell" wrote: klem kedidelhopper wrote: We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny * *Is the speed controler made for induction motors? How would a speed controller made for induction motors differ from say an ordinary lamp dimmer? * *Lamp dimmers are simple phase controllers. *They aren't designed for inductive loads. That's why most light dimmers can't be used on Florescent lights. *They can cause the motor to overheat at some speeds, and cause it to be noisy or erratic at low speeds. Leviton makes variable speed fan controls with a slider to set the speed. You can get them at HD, Lowes or a lot of other building supply stores. http://www.leviton.com/OA_HTML/ibeCCtpSctDspRte.jsp?section=10857&min.... http://www.lowes.com/SearchCatalogDisplay?Ntt=speed+control&langId=-1... http://www.homedepot.com/webapp/wcs/stores/servlet/Search?keyword=spe.... -- It's easy to think outside the box, when you have a cutting torch. Thanks Michael for sending me those dimmer links. They are pricey though... Lenny |
#8
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ceiling fan buzzing
On Jul 18, 9:22*am, klem kedidelhopper
wrote: On Jul 17, 6:30*am, "Michael A. Terrell" wrote: klem kedidelhopper wrote: On Jul 16, 7:35 pm, "Michael A. Terrell" wrote: klem kedidelhopper wrote: We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny * *Is the speed controler made for induction motors? How would a speed controller made for induction motors differ from say an ordinary lamp dimmer? * *Lamp dimmers are simple phase controllers. *They aren't designed for inductive loads. That's why most light dimmers can't be used on Florescent lights. *They can cause the motor to overheat at some speeds, and cause it to be noisy or erratic at low speeds. Leviton makes variable speed fan controls with a slider to set the speed. You can get them at HD, Lowes or a lot of other building supply stores. http://www.leviton.com/OA_HTML/ibeCCtpSctDspRte.jsp?section=10857&min... http://www.lowes.com/SearchCatalogDisplay?Ntt=speed+control&langId=-1... http://www.homedepot.com/webapp/wcs/stores/servlet/Search?keyword=spe... -- It's easy to think outside the box, when you have a cutting torch. Thanks Michael for sending me those dimmer links. They are pricey though... Lenny I did find the Leviton but it may not be a continuously variable unit. I'll have to go look at them. Lenny |
#9
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ceiling fan buzzing
On Mon, 18 Jul 2011 06:31:03 -0700 (PDT), klem kedidelhopper
wrote: On Jul 18, 9:22*am, klem kedidelhopper wrote: On Jul 17, 6:30*am, "Michael A. Terrell" wrote: klem kedidelhopper wrote: On Jul 16, 7:35 pm, "Michael A. Terrell" wrote: klem kedidelhopper wrote: We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny * *Is the speed controler made for induction motors? How would a speed controller made for induction motors differ from say an ordinary lamp dimmer? * *Lamp dimmers are simple phase controllers. *They aren't designed for inductive loads. That's why most light dimmers can't be used on Florescent lights. *They can cause the motor to overheat at some speeds, and cause it to be noisy or erratic at low speeds. Leviton makes variable speed fan controls with a slider to set the speed. You can get them at HD, Lowes or a lot of other building supply stores. http://www.leviton.com/OA_HTML/ibeCCtpSctDspRte.jsp?section=10857&min... http://www.lowes.com/SearchCatalogDisplay?Ntt=speed+control&langId=-1... http://www.homedepot.com/webapp/wcs/stores/servlet/Search?keyword=spe... -- It's easy to think outside the box, when you have a cutting torch. Thanks Michael for sending me those dimmer links. They are pricey though... Lenny I did find the Leviton but it may not be a continuously variable unit. I'll have to go look at them. Lenny I had a fan that was noisy like that, and stuck a 5-10 uF capacitor in series with the motor. You can't use the dimmer - so you need a switch to hook the fan either to the controller or the series cap. It runs quite slowly, and no buzzing. Make sure the capacitor is designed for line use ..... 250vac or 600vdc should be OK. If it fails, the fan will just run at full speed. The only worry would be if it were to get hot say from internal arcing or something wierd like that. To be one the safe side use a U/L approved or type Z capacitor. You can cause the cap and inductance of the fan to resonate.... That will cause voltages greater than the line voltage to appear across the fan motor, and it go fast, and overheat. Try a few capacitors, starting at 1uf, and increase until you get the speed you want. Some fans have a switch that gives 3-4 speeds, with a series cap, you can effectively get a much slower range of speeds, and thereby not need to use a dimmer type speed controller. Paul G. |
#10
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ceiling fan buzzing
On Mon, 18 Jul 2011 21:35:26 -0300, Paul G.
wrote: On Mon, 18 Jul 2011 06:31:03 -0700 (PDT), klem kedidelhopper wrote: On Jul 18, 9:22*am, klem kedidelhopper wrote: On Jul 17, 6:30*am, "Michael A. Terrell" wrote: klem kedidelhopper wrote: On Jul 16, 7:35 pm, "Michael A. Terrell" wrote: klem kedidelhopper wrote: We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny * *Is the speed controler made for induction motors? How would a speed controller made for induction motors differ from say an ordinary lamp dimmer? * *Lamp dimmers are simple phase controllers. *They aren't designed for inductive loads. That's why most light dimmers can't be used on Florescent lights. *They can cause the motor to overheat at some speeds, and cause it to be noisy or erratic at low speeds. Leviton makes variable speed fan controls with a slider to set the speed. You can get them at HD, Lowes or a lot of other building supply stores. http://www.leviton.com/OA_HTML/ibeCCtpSctDspRte.jsp?section=10857&min... http://www.lowes.com/SearchCatalogDisplay?Ntt=speed+control&langId=-1... http://www.homedepot.com/webapp/wcs/stores/servlet/Search?keyword=spe... -- It's easy to think outside the box, when you have a cutting torch. Thanks Michael for sending me those dimmer links. They are pricey though... Lenny I did find the Leviton but it may not be a continuously variable unit. I'll have to go look at them. Lenny I had a fan that was noisy like that, and stuck a 5-10 uF capacitor in series with the motor. You can't use the dimmer - so you need a switch to hook the fan either to the controller or the series cap. It runs quite slowly, and no buzzing. Make sure the capacitor is designed for line use ..... 250vac or 600vdc should be OK. If it fails, the fan will just run at full speed. The only worry would be if it were to get hot say from internal arcing or something wierd like that. To be one the safe side use a U/L approved or type Z capacitor. You can cause the cap and inductance of the fan to resonate.... That will cause voltages greater than the line voltage to appear across the fan motor, and it go fast, and overheat. Try a few capacitors, starting at 1uf, and increase until you get the speed you want. Some fans have a switch that gives 3-4 speeds, with a series cap, you can effectively get a much slower range of speeds, and thereby not need to use a dimmer type speed controller. Paul G. That should be a "X" type capacitor, not a "Z" type. It's questionable that you need either X or Y types. From an Illinois Capacitor blurb on capacitors: " These capacitors are divided into 2 classifications, X and Y. X class capacitors are capacitors that are connected line to line and in the event of failure of the capacitor the potential for electrical shock is not present. X capacitors are further subdivided into three subcategories X1, X2 and X3. X1 capacitors are used where the peak voltage the capacitors will be greater than 2500 volts and less than 4000V. Class X2 capacitors are in applications where the peak voltage is equal to below 2500 volts. X3 capacitors are used where the peak voltage is less than or equal to 1200 volts. X2 capacitors are the most common. Y capacitors on the other hand are connected from line to ground. They are typically a very low capacitance value. In the event a Y capacitor fails the potential for electrical shock is present. Y capacitors are also subdivided into four subcategories, Y1, Y2, Y3 and Y4. Y1 capacitors are used with voltages up 500Vac, Y2 are used with voltages up to 300Vac,Y3 are used with voltages up to 250Vac and Y4 capacitors are used up to 150Vac. X class capacitors are rated up to 660Vac and Y capacitors are manufactured with voltage ratings up to 440Vac. X class capacitors are manufactured with a variety of dielectric materials. This includes polyester, polypropylene, ceramic and paper while Y capacitors are typically produced out of ceramic and paper dielectrics. With the exception of ceramics the capacitors are produced using metallized materials and may be impregnated with epoxy or mineral oils." |
#11
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ceiling fan buzzing
On Jul 18, 9:01*pm, Paul G. wrote:
On Mon, 18 Jul 2011 21:35:26 -0300, Paul G. wrote: On Mon, 18 Jul 2011 06:31:03 -0700 (PDT), klem kedidelhopper wrote: On Jul 18, 9:22*am, klem kedidelhopper wrote: On Jul 17, 6:30*am, "Michael A. Terrell" wrote: klem kedidelhopper wrote: On Jul 16, 7:35 pm, "Michael A. Terrell" wrote: klem kedidelhopper wrote: We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny * *Is the speed controler made for induction motors? How would a speed controller made for induction motors differ from say an ordinary lamp dimmer? * *Lamp dimmers are simple phase controllers. *They aren't designed for inductive loads. That's why most light dimmers can't be used on Florescent lights. *They can cause the motor to overheat at some speeds, and cause it to be noisy or erratic at low speeds. Leviton makes variable speed fan controls with a slider to set the speed. You can get them at HD, Lowes or a lot of other building supply stores. http://www.leviton.com/OA_HTML/ibeCCtpSctDspRte.jsp?section=10857&min... http://www.lowes.com/SearchCatalogDisplay?Ntt=speed+control&langId=-1... http://www.homedepot.com/webapp/wcs/stores/servlet/Search?keyword=spe... -- It's easy to think outside the box, when you have a cutting torch. Thanks Michael for sending me those dimmer links. They are pricey though... Lenny I did find the Leviton but it may not be a continuously variable unit. I'll have to go look at them. Lenny * I had a fan that was noisy like that, and stuck a 5-10 uF capacitor in series with the motor. You can't use the dimmer - so you need a switch to hook the fan either to the controller or the series cap. It runs quite slowly, and no buzzing. Make sure the capacitor is designed for line use ..... 250vac or 600vdc should be OK. If it fails, the fan will just run at full speed. The only worry would be if it were to get hot say from internal arcing or something wierd like that. To be one the safe side use a U/L approved or type Z capacitor. * You can cause the cap and inductance of the fan to resonate.... That will cause voltages greater than the line voltage to appear across the fan motor, and it go fast, and overheat. Try a few capacitors, starting at 1uf, and increase until you get the speed you want. * Some fans have a switch that gives 3-4 speeds, with a series cap, you can effectively get a much slower range of speeds, and thereby not need to use a dimmer type speed controller. Paul G. * That should be a "X" type capacitor, not a "Z" type. It's questionable that you need either X or Y types. * From an Illinois Capacitor blurb on capacitors: " These capacitors are divided into 2 classifications, X and Y. X class capacitors are capacitors that are connected line to line and in the event of failure of the capacitor the potential for electrical shock is not present. X capacitors are further subdivided into three subcategories X1, X2 and X3. X1 capacitors are used where the peak voltage the capacitors will be greater than 2500 volts and less than 4000V. Class X2 capacitors are in applications where the peak voltage is equal to below 2500 volts. X3 capacitors are used where the peak voltage is less than or equal to 1200 volts. X2 capacitors are the most common. Y capacitors on the other hand are connected from line to ground. They are typically a very low capacitance value. In the event a Y capacitor fails the potential for electrical shock is present. Y capacitors are also subdivided into four subcategories, Y1, Y2, Y3 and Y4. Y1 capacitors are used with voltages up 500Vac, Y2 are used with voltages up to 300Vac,Y3 are used with voltages up to 250Vac and Y4 capacitors are used up to 150Vac. X class capacitors are rated up to 660Vac and Y capacitors are manufactured with voltage ratings up to 440Vac. X class capacitors are manufactured with a variety of dielectric materials. This includes polyester, polypropylene, ceramic and paper while Y capacitors are typically produced out of ceramic and paper dielectrics. With the exception of ceramics the capacitors are produced using metallized materials and may be impregnated with epoxy or mineral oils." I'm thinking that the fan draws about 1.0 amp. Therefore that current would be passing through the capacitor. I do have lots of capacitors as well as a 5 position tapped transformer type speed control from another fan. The problem with that control though is that slow speed is not slow enough. Perhaps I could put the capacitor in series with slow position and see what that will do. I never thought of doing this. Lenny |
#12
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ceiling fan buzzing
Much depends upon what type of motor is in the ceiling fan. There are more
than one type of AC motors without brushes. Klem/Lenny hasn't revealed what type of AC motor he's referring to.. nor anything specific regarding the "generic" controller that wasn't supplied with the fan. -- Cheers, WB .............. "Paul G." wrote in message ... I had a fan that was noisy like that, and stuck a 5-10 uF capacitor in series with the motor. You can't use the dimmer - so you need a switch to hook the fan either to the controller or the series cap. It runs quite slowly, and no buzzing. Make sure the capacitor is designed for line use ..... 250vac or 600vdc should be OK. If it fails, the fan will just run at full speed. The only worry would be if it were to get hot say from internal arcing or something wierd like that. To be one the safe side use a U/L approved or type Z capacitor. You can cause the cap and inductance of the fan to resonate.... That will cause voltages greater than the line voltage to appear across the fan motor, and it go fast, and overheat. Try a few capacitors, starting at 1uf, and increase until you get the speed you want. Some fans have a switch that gives 3-4 speeds, with a series cap, you can effectively get a much slower range of speeds, and thereby not need to use a dimmer type speed controller. Paul G. On Mon, 18 Jul 2011 06:31:03 -0700 (PDT), klem kedidelhopper wrote: On Jul 18, 9:22 am, klem kedidelhopper wrote: Thanks Michael for sending me those dimmer links. They are pricey though... Lenny |
#13
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ceiling fan buzzing
On Jul 19, 11:25*am, "Wild_Bill" wrote:
Much depends upon what type of motor is in the ceiling fan. There are more than one type of AC motors without brushes. Klem/Lenny hasn't revealed what type of AC motor he's referring to.. nor anything specific regarding the "generic" controller that wasn't supplied with the fan. -- Cheers, WB ............. "Paul G." wrote in message ... * I had a fan that was noisy like that, and stuck a 5-10 uF capacitor in series with the motor. You can't use the dimmer - so you need a switch to hook the fan either to the controller or the series cap. It runs quite slowly, and no buzzing. Make sure the capacitor is designed for line use ..... 250vac or 600vdc should be OK. If it fails, the fan will just run at full speed. The only worry would be if it were to get hot say from internal arcing or something wierd like that. To be one the safe side use a U/L approved or type Z capacitor. * You can cause the cap and inductance of the fan to resonate.... That will cause voltages greater than the line voltage to appear across the fan motor, and it go fast, and overheat. Try a few capacitors, starting at 1uf, and increase until you get the speed you want. * Some fans have a switch that gives 3-4 speeds, with a series cap, you can effectively get a much slower range of speeds, and thereby not need to use a dimmer type speed controller. Paul G. On Mon, 18 Jul 2011 06:31:03 -0700 (PDT), klem kedidelhopper wrote: On Jul 18, 9:22 am, klem kedidelhopper wrote: Thanks Michael for sending me those dimmer links. They are pricey though... Lenny Well I don't really know what kind of a motor this is. I purchased the fan as new surplus and it never came with a controller. It looks like my other fans I use in the house but from a different manufacturer. There are three metal blades, very plain looking "airplane propeller" style, hangs from the ceiling about 1 foot down. The controller for the other fans looks like a tapped autoformer with a 5 position switch. Lenny |
#14
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ceiling fan buzzing
On Jul 17, 2:12*am, lsmartino wrote:
On 16 jul, 09:27, klem kedidelhopper wrote: We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny A 120vac ceiling fan motor uses a pancake induction motor which can't be used with DC. *I have seen wall rehostats for sale at hardware stores to be used with ceiling fans. Some of them have two controls, one for the ceiling fan lamp light and another for the fan. These can be installed inside a 2x4 box. The ones I have seen are manufactured by Ace Hardware. Good luck! Ceiling fans sold in Australia, typically switch between a couple of non polar mains rated capacitors in series with the motor. a few UF from memory. can look later at one if you really want to know. (note here is 50hz, you might need different values for 60hz). The other type of speed control that is used here - but not as common is the same as a light dimmer except there is a resistor in series with the pot to ensure a minimum speed to prevent the motor from stalling and overheating due to insufficient speed setting for it to start rotating from a dead stop. |
#15
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ceiling fan buzzing
On 19 Jul 11 at group /sci/electronics/repair in article (Wild_Bill) wrote: Much depends upon what type of motor is in the ceiling fan. There are more than one type of AC motors without brushes. Klem/Lenny hasn't revealed what type of AC motor he's referring to.. nor anything specific regarding the "generic" controller that wasn't supplied with the fan. Here in PY there are lots of ceiling fans from Wahson/China. 230V/50Hz They use a separate autotransformer in an aluminium housing (15x9x4 cm) as controller. It is in series with the motor and has 7 taps and a turning switch with weird numbered positions from 0 = off and 1=max ... 7=slowest speed! The motor so gets between 230V and down to some 80V. My 5 Wahsons did not buzzing, even in slowest speed. However I have 2 fans (also made in china) with no external controller but a small hanging line which switches between 3 different speeds by taping different positions in the motor winding. They both are buzzing in speeds below max. I think thats in the remaining active sectors of the winding. None of these motors have brushes. Saludos Wolfgang -- Meine 7 Sinne: Unsinn, Schwachsinn, Blödsinn, Wahnsinn, Stumpfsinn, Irrsinn, Lötzinn. Wolfgang Allinger Paraguay reply Adresse gesetzt ! ca. 15h00..21h00 MEZ SKYPE:wolfgang.allinger |
#16
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ceiling fan buzzing
On Jul 22, 8:44*am, (Wolfgang Allinger) wrote:
*On 19 Jul 11 at group /sci/electronics/repair in article *(Wild_Bill) *wrote: Much depends upon what type of motor is in the ceiling fan. There are more than one type of AC motors without brushes. Klem/Lenny hasn't revealed what type of AC motor he's referring to.. nor anything specific regarding the "generic" controller that wasn't supplied with the fan. Here in PY there are lots of ceiling fans from Wahson/China. 230V/50Hz They use a separate autotransformer in an aluminium housing (15x9x4 cm) * as controller. It is in series with the motor and has 7 taps and a turning switch with * weird numbered positions from 0 = off and 1=max ... 7=slowest speed! The motor so gets between 230V and down to some 80V. My 5 Wahsons did not buzzing, even in slowest speed. However I have 2 fans (also made in china) with no external controller * but a small hanging line which switches between 3 different speeds by * taping different positions in the motor winding. They both are buzzing * in speeds below max. I think thats in the remaining active sectors of * the winding. None of these motors have brushes. Saludos Wolfgang -- Meine 7 Sinne: Unsinn, Schwachsinn, Blödsinn, Wahnsinn, Stumpfsinn, Irrsinn, Lötzinn.. Wolfgang Allinger * Paraguay * * * * * * reply Adresse gesetzt ! ca. 15h00..21h00 MEZ *SKYPE:wolfgang.allinger I would like to try the trick with the capacitor in series with the slowest tap on the speed control however I am a bit unclear as to how to "size" the capacitor. By "size" I mean that it seems like if the motor draws one amp for example, (and I will confirm that first), I will need a capacitor that can handle more than that amount of current flowing through it. I remember dealing with this sort of thing in electronics school, but admittedly that was a very long time ago and I've forgotten how to work this out. For instance, I have a 4uf 250V AC capacitor that I would like to try. This part is designed for motor starting. This is a fairly large capacitor. The control box measures approximately 8" x 6" X 3". Most of that space is taken up by the switch and transformer. There would not be room inside for anything this large. Or do I need to use anything this large? Thanks, Lenny |
#17
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ceiling fan buzzing
On 23 Jul 11 at group /sci/electronics/repair in article (klem kedidelhopper) wrote: On Jul 22, 8:44 am, (Wolfgang Allinger) wrote: On 19 Jul 11 at group /sci/electronics/repair in article Here in PY there are lots of ceiling fans from Wahson/China. 230V/50Hz They use a separate autotransformer in an aluminium housing (15x9x4 cm) as controller. It is in series with the motor and has 7 taps and a turning switch with weird numbered positions from 0 = off and 1=max ... 7=slowest speed! The motor so gets between 230V and down to some 80V. I would like to try the trick with the capacitor in series with the slowest tap on the speed control Try if it works and the Motor starts in this position. If not, it might become very hot after it stops at a PWR out and return of PWR. In the worst case, you will see firefigters at your home after you return from a party Saludos Wolfgang -- Meine 7 Sinne: Unsinn, Schwachsinn, Blödsinn, Wahnsinn, Stumpfsinn, Irrsinn, Lötzinn. Wolfgang Allinger Paraguay reply Adresse gesetzt ! ca. 15h00..21h00 MEZ SKYPE:wolfgang.allinger |
#18
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ceiling fan buzzing
On Jul 23, 8:35*am, (Wolfgang Allinger) wrote:
*On 23 Jul 11 at group /sci/electronics/repair in article *(klem kedidelhopper) *wrote: On Jul 22, 8:44 am, (Wolfgang Allinger) wrote: *On 19 Jul 11 at group /sci/electronics/repair in article Here in PY there are lots of ceiling fans from Wahson/China. 230V/50Hz They use a separate autotransformer in an aluminium housing (15x9x4 cm) as controller. It is in series with the motor and has 7 taps and a turning switch with weird numbered positions from 0 = off and 1=max ... 7=slowest speed! The motor so gets between 230V and down to some 80V. I *would like to try the trick with the capacitor in series with the slowest tap on the speed control Try if it works and the Motor starts in this position. If not, it might * become very hot after it stops at a PWR out and return of PWR. In the worst case, you will see firefigters at your home after you * return from a party Saludos Wolfgang -- Meine 7 Sinne: Unsinn, Schwachsinn, Blödsinn, Wahnsinn, Stumpfsinn, Irrsinn, Lötzinn.. Wolfgang Allinger * Paraguay * * * * * * reply Adresse gesetzt ! ca. 15h00..21h00 MEZ *SKYPE:wolfgang.allinger |
#19
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ceiling fan buzzing
On Jul 23, 8:35*am, (Wolfgang Allinger) wrote:
*On 23 Jul 11 at group /sci/electronics/repair in article *(klem kedidelhopper) *wrote: On Jul 22, 8:44 am, (Wolfgang Allinger) wrote: *On 19 Jul 11 at group /sci/electronics/repair in article Here in PY there are lots of ceiling fans from Wahson/China. 230V/50Hz They use a separate autotransformer in an aluminium housing (15x9x4 cm) as controller. It is in series with the motor and has 7 taps and a turning switch with weird numbered positions from 0 = off and 1=max ... 7=slowest speed! The motor so gets between 230V and down to some 80V. I *would like to try the trick with the capacitor in series with the slowest tap on the speed control Try if it works and the Motor starts in this position. If not, it might * become very hot after it stops at a PWR out and return of PWR. In the worst case, you will see firefigters at your home after you * return from a party Saludos Wolfgang -- Meine 7 Sinne: Unsinn, Schwachsinn, Blödsinn, Wahnsinn, Stumpfsinn, Irrsinn, Lötzinn.. Wolfgang Allinger * Paraguay * * * * * * reply Adresse gesetzt ! ca. 15h00..21h00 MEZ *SKYPE:wolfgang.allinger Why don't I just burn my house down before I leave for the party. That way at least there won't be any surprises when I return.....Lenny |
#20
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ceiling fan buzzing
http://www.hurontel.on.ca/~taitg/pages/cfan.html
The above should give you some ideas of the speed control methods used for ceiling fans. Most of the infinately variable ones will end up with noise. Changing the caps will get you a lower speed. Notice that there are different methods and not one size fits all. Also at www.ceilingfanparts.com the spped switches are quite pecular. |
#21
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ceiling fan buzzing
On Jul 23, 10:18*pm, klem kedidelhopper
wrote: On Jul 22, 8:44*am, (Wolfgang Allinger) wrote: *On 19 Jul 11 at group /sci/electronics/repair in article *(Wild_Bill) *wrote: Much depends upon what type of motor is in the ceiling fan. There are more than one type of AC motors without brushes. Klem/Lenny hasn't revealed what type of AC motor he's referring to.. nor anything specific regarding the "generic" controller that wasn't supplied with the fan. Here in PY there are lots of ceiling fans from Wahson/China. 230V/50Hz They use a separate autotransformer in an aluminium housing (15x9x4 cm) * as controller. It is in series with the motor and has 7 taps and a turning switch with * weird numbered positions from 0 = off and 1=max ... 7=slowest speed! The motor so gets between 230V and down to some 80V. My 5 Wahsons did not buzzing, even in slowest speed. However I have 2 fans (also made in china) with no external controller * but a small hanging line which switches between 3 different speeds by * taping different positions in the motor winding. They both are buzzing * in speeds below max. I think thats in the remaining active sectors of * the winding. None of these motors have brushes. Saludos Wolfgang *-- Meine 7 Sinne: Unsinn, Schwachsinn, Blödsinn, Wahnsinn, Stumpfsinn, Irrsinn, Lötzinn. |
#22
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ceiling fan buzzing
On Jul 25, 6:28*am, KR wrote:
On Jul 23, 10:18*pm, klem kedidelhopper wrote: On Jul 22, 8:44*am, (Wolfgang Allinger) wrote: *On 19 Jul 11 at group /sci/electronics/repair in article *(Wild_Bill) *wrote: Much depends upon what type of motor is in the ceiling fan. There are more than one type of AC motors without brushes. Klem/Lenny hasn't revealed what type of AC motor he's referring to.. nor anything specific regarding the "generic" controller that wasn't supplied with the fan. Here in PY there are lots of ceiling fans from Wahson/China. 230V/50Hz They use a separate autotransformer in an aluminium housing (15x9x4 cm) * as controller. It is in series with the motor and has 7 taps and a turning switch with * weird numbered positions from 0 = off and 1=max ... 7=slowest speed! The motor so gets between 230V and down to some 80V. My 5 Wahsons did not buzzing, even in slowest speed. However I have 2 fans (also made in china) with no external controller * but a small hanging line which switches between 3 different speeds by * taping different positions in the motor winding. They both are buzzing * in speeds below max. I think thats in the remaining active sectors of * the winding. None of these motors have brushes. Saludos Wolfgang *-- Meine 7 Sinne: Unsinn, Schwachsinn, Blödsinn, Wahnsinn, Stumpfsinn, Irrsinn, Lötzinn. Wolfgang Allinger * Paraguay * * * * * * reply Adresse gesetzt ! ca. 15h00..21h00 MEZ *SKYPE:wolfgang.allinger I *would like to try the trick with the capacitor in series with the slowest tap on the speed control however I am a bit unclear as to *how to "size" the capacitor. By "size" I mean that it seems like if the motor draws one amp for example, (and I will confirm that first), I will need a capacitor that can handle more than that amount of current flowing through it. I remember dealing with this sort of thing in electronics school, but admittedly that was a very long time ago and I've forgotten how to work this out. For instance, I have a 4uf 250V AC capacitor that I would like to try. This part is designed for motor starting. This is a fairly large capacitor. The control box measures approximately 8" x 6" X 3". Most of that space is taken up by the switch and transformer. There would not be room inside for anything this large. Or do I need to use anything this large? Thanks, Lenny Took a look inside a controller today, they have 1.8UF and 3.6UF (at 50hz) capacitors *(motor was labelled 65w) Another thing you could to, if you have access to someone who is reasonably accurate in metal folding, is to fold the fan blades down a little bit more to change the pitch. (alternately you might try packing washers between the blade and the motor under the mounting screws to tilt it slightly more - dont know if it would work but worth a try) A friend found that out the hard way years back when unknowingly put 4 blades meant for a 3 blade fan onto a 4 blade fan body and nearly drove himself mad trying to work out why he couldnt get it to go fast enough. He had picked up several fans and a box of blades free from a place that was being renovated and just picked out 4 blades that looked the same. It was a very small difference in blade angle, but knocked off an enormous amount of speed But wouldn't that also load the motor more than it should be? Lenny |
#23
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ceiling fan buzzing
On Jul 26, 12:28*am, klem kedidelhopper
wrote: On Jul 25, 6:28*am, KR wrote: On Jul 23, 10:18*pm, klem kedidelhopper wrote: On Jul 22, 8:44*am, (Wolfgang Allinger) wrote: *On 19 Jul 11 at group /sci/electronics/repair in article *(Wild_Bill) *wrote: Much depends upon what type of motor is in the ceiling fan. There are more than one type of AC motors without brushes. Klem/Lenny hasn't revealed what type of AC motor he's referring to... nor anything specific regarding the "generic" controller that wasn't supplied with the fan. Here in PY there are lots of ceiling fans from Wahson/China. 230V/50Hz They use a separate autotransformer in an aluminium housing (15x9x4 cm) * as controller. It is in series with the motor and has 7 taps and a turning switch with * weird numbered positions from 0 = off and 1=max ... 7=slowest speed! The motor so gets between 230V and down to some 80V. My 5 Wahsons did not buzzing, even in slowest speed. However I have 2 fans (also made in china) with no external controller * but a small hanging line which switches between 3 different speeds by * taping different positions in the motor winding. They both are buzzing * in speeds below max. I think thats in the remaining active sectors of * the winding. None of these motors have brushes. Saludos Wolfgang *-- Meine 7 Sinne: Unsinn, Schwachsinn, Blödsinn, Wahnsinn, Stumpfsinn, Irrsinn, Lötzinn. Wolfgang Allinger * Paraguay * * * * * * reply Adresse gesetzt ! ca. 15h00..21h00 MEZ *SKYPE:wolfgang.allinger I *would like to try the trick with the capacitor in series with the slowest tap on the speed control however I am a bit unclear as to *how to "size" the capacitor. By "size" I mean that it seems like if the motor draws one amp for example, (and I will confirm that first), I will need a capacitor that can handle more than that amount of current flowing through it. I remember dealing with this sort of thing in electronics school, but admittedly that was a very long time ago and I've forgotten how to work this out. For instance, I have a 4uf 250V AC capacitor that I would like to try.. This part is designed for motor starting. This is a fairly large capacitor. The control box measures approximately 8" x 6" X 3". Most of that space is taken up by the switch and transformer. There would not be room inside for anything this large. Or do I need to use anything this large? Thanks, Lenny Took a look inside a controller today, they have 1.8UF and 3.6UF (at 50hz) capacitors *(motor was labelled 65w) Another thing you could to, if you have access to someone who is reasonably accurate in metal folding, is to fold the fan blades down a little bit more to change the pitch. (alternately you might try packing washers between the blade and the motor under the mounting screws to tilt it slightly more - dont know if it would work but worth a try) A friend found that out the hard way years back when unknowingly put 4 blades meant for a 3 blade fan onto a 4 blade fan body and nearly drove himself mad trying to work out why he couldnt get it to go fast enough. He had picked up several fans and a box of blades free from a place that was being renovated and just picked out 4 blades that looked the same. It was a very small difference in blade angle, but knocked off an enormous amount of speed But wouldn't that also load the motor more than it should be? *Lenny definitely would, but whether or not it damages the motor is another matter. as long as there is enough airflow around it to not let it overheat it should be ok ?. |
#24
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ceiling fan buzzing
"klem kedidelhopper" wrote in message ... We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny Klem, First off, remove the light dimmer from the circuit. Dimmers are known to cause hum/buzzing in ceiling fan induction motors. Ceiling fan induction motors like sine waves. If the fan still buzzes on pure sine wave AC current, the motor has loose/separated stator laminations or loose winding coils on the stator; this is usually not repairable, although a good lacquer bath could theoretically tighten it up. The older spinner fans (especially ones that do not have a pull chain switch to proivde the lower speeds) used a multiple tapped transformer to provide the lower voltages. It was often too large to fit within a standard wall switch box and was designed for surface mounting on the wall. There are controls made specifically for ceiling fans that are incremental (not continuously variable) that provide reduced voltages for the lower speeds but keep the sine wave intact. Transformers are no longer used. Using a capacitor inline with the power to provide the lower speeds is the preferred method in fan manufacturing today. Today's fans and fan controls use a dual stage capacitor - paired together in parallel for Medium and one stage for Low Speed. For 120VAC 60Hz, the capacitor's rated voltage should be at least 240VAC for the speed control capacitors. Speed capacitor values range from 1.5µF to 12µF, with the most common falling between 3µ and 5µ. There should be a running capacitor wired to one end of one motor winding, probably mounted above the motor. The µF value of this capacitor is a good starting point for low speed from speed control capacitors. Many "universal" ceiling fan controls use 5µF + 5µF or 5µF + 6µF dual capacitors. This is around 2.5µF for Medium and 5µF or 6µF for Low Speed. Slowing the motor beyond the natural Low Speed range, to a "crawl" as it were, with a large capacitor value will likely produce some harmonic noise anyway, but should not buzz. The numbering sequence for fan controls always starts at 1 for High Speed because fans should always be started on High Speed then lowered to the desired speed. (At a dead stop, the motor is an effective, coupled inductor, add the speed capacitors and running capacitor, and it can create voltages in the circuit higher than component ratings.) Hope this helps Scott Dunedin, FL |
#25
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ceiling fan buzzing
"klem kedidelhopper" wrote in message ... On Aug 1, 5:25 pm, "Anon" wrote: "klem kedidelhopper" wrote in message ... We have a ceiling fan in our bedroom that we sometimes like to run at very slow speed at night. The fan was purchased as new surplus many years ago and never came with a speed control. So I have been using a generic solid state speed controller. With this unit we are able to take the unit down to complete "crawl" however there has always been a slight rhythmic buzzing noise whose loudness and duty cycle are both directly proportional to the motor speed. I know it's related to the pulse type of control I'm using but short of just using a variac or a rheostat for that matter, does anyone know of a method to achieve a very slow speed without the noise? Also this motor has no brushes and so even though its not labeled as such I wonder if it could be a "Universal" type of motor that could run on DC? It wouldn't take much to put a bridge and perhaps even a filter in the electrical box ahead of the motor. I'm thinking that DC operation could possibly be quieter. Thanks, Lenny Klem, First off, remove the light dimmer from the circuit. Dimmers are known to cause hum/buzzing in ceiling fan induction motors. Ceiling fan induction motors like sine waves. If the fan still buzzes on pure sine wave AC current, the motor has loose/separated stator laminations or loose winding coils on the stator; this is usually not repairable, although a good lacquer bath could theoretically tighten it up. The older spinner fans (especially ones that do not have a pull chain switch to proivde the lower speeds) used a multiple tapped transformer to provide the lower voltages. It was often too large to fit within a standard wall switch box and was designed for surface mounting on the wall. There are controls made specifically for ceiling fans that are incremental (not continuously variable) that provide reduced voltages for the lower speeds but keep the sine wave intact. Transformers are no longer used. Using a capacitor inline with the power to provide the lower speeds is the preferred method in fan manufacturing today. Today's fans and fan controls use a dual stage capacitor - paired together in parallel for Medium and one stage for Low Speed. For 120VAC 60Hz, the capacitor's rated voltage should be at least 240VAC for the speed control capacitors. Speed capacitor values range from 1.5µF to 12µF, with the most common falling between 3µ and 5µ. There should be a running capacitor wired to one end of one motor winding, probably mounted above the motor. The µF value of this capacitor is a good starting point for low speed from speed control capacitors. Many "universal" ceiling fan controls use 5µF + 5µF or 5µF + 6µF dual capacitors. This is around 2.5µF for Medium and 5µF or 6µF for Low Speed. Slowing the motor beyond the natural Low Speed range, to a "crawl" as it were, with a large capacitor value will likely produce some harmonic noise anyway, but should not buzz. The numbering sequence for fan controls always starts at 1 for High Speed because fans should always be started on High Speed then lowered to the desired speed. (At a dead stop, the motor is an effective, coupled inductor, add the speed capacitors and running capacitor, and it can create voltages in the circuit higher than component ratings.) Hope this helps Scott Dunedin, FL Thank you very much for the explanation Scott. That explains a great many things. My speed controls on these fans are the large tapped transformers exactly as you described. But now what about the current flowing through the capacitor? Is this a concern when selecting a capacitor for the application? Lenny Klem, Typically ceiling fan motors pull less than 1 amp current at 120V and the capacitors used in ceiling fans are large, metallized poly film type AC capacitors. We've never had to consider the current with these capacitors. Scott |
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