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How Does an Electric Motor Know How Much Electricity Is Needed

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  How Does an Electric Motor Know How Much Electricity Is Needed "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-04-24 09:39 -0700
    How Does an Electric Motor Know How Much Electricity Is Needed HVAC <mr.hvac@gmail.com> - 2016-04-24 09:56 -0700
      Re: How Does an Electric Motor Know How Much Electricity Is Needed benj <nobodyxx@gmail> - 2016-04-24 23:52 -0400
        Re: How Does an Electric Motor Know How Much Electricity Is Needed "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-04-25 11:49 -0700
          Re: How Does an Electric Motor Know How Much Electricity Is Needed Sam Wormley <swormley1@gmail.com> - 2016-04-25 14:37 -0500
            Re: How Does an Electric Motor Know How Much Electricity Is Needed Sergio <invalid@invalid.com> - 2016-04-25 21:14 -0500
    Re: How Does an Electric Motor Know How Much Electricity Is Needed Sergio <invalid@invalid.com> - 2016-04-24 12:17 -0500
    Re: How Does an Electric Motor Know How Much Electricity Is Needed Sam Wormley <swormley1@gmail.com> - 2016-04-24 14:14 -0500
    Re: How Does an Electric Motor Know How Much Electricity Is Needed Double-A <double-a3@hush.com> - 2016-04-24 13:41 -0700
      Re: How Does an Electric Motor Know How Much Electricity Is Needed "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-04-24 16:19 -0700
        Re: How Does an Electric Motor Know How Much Electricity Is Needed HVAC <mr.hvac@gmail.com> - 2016-04-24 16:45 -0700
        Re: How Does an Electric Motor Know How Much Electricity Is Needed "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-04-25 11:45 -0700
          Re: How Does an Electric Motor Know How Much Electricity Is Needed Sam Wormley <swormley1@gmail.com> - 2016-04-25 14:25 -0500
            Re: How Does an Electric Motor Know How Much Electricity Is Needed jimp@specsol.spam.sux.com - 2016-04-25 19:39 +0000
            Re: How Does an Electric Motor Know How Much Electricity Is Needed Double-A <double-a3@hush.com> - 2016-04-25 17:08 -0700
              Re: How Does an Electric Motor Know How Much Electricity Is Needed Sam Wormley <swormley1@gmail.com> - 2016-04-25 19:16 -0500
                Re: How Does an Electric Motor Know How Much Electricity Is Needed jimp@specsol.spam.sux.com - 2016-04-26 00:41 +0000
                Re: How Does an Electric Motor Know How Much Electricity Is Needed Wally W. <ww84wa@aim.com> - 2016-04-25 23:05 -0400
                  Re: How Does an Electric Motor Know How Much Electricity Is Needed benj <nobodyxx@gmail> - 2016-04-26 03:11 -0400
                    Re: How Does an Electric Motor Know How Much Electricity Is Needed Sergio <invalid@invalid.com> - 2016-04-26 17:29 -0500
                  Re: How Does an Electric Motor Know How Much Electricity Is Needed Double-A <double-a3@hush.com> - 2016-04-26 13:11 -0700
                    Re: How Does an Electric Motor Know How Much Electricity Is Needed Sam Wormley <swormley1@gmail.com> - 2016-04-26 19:03 -0500
            Re: How Does an Electric Motor Know How Much Electricity Is Needed benj <nobodyxx@gmail> - 2016-04-25 21:59 -0400
    Re: How Does an Electric Motor Know How Much Electricity Is Needed Sylvia Else <sylvia@not.at.this.address> - 2016-04-27 11:33 +1000
      Re: How Does an Electric Motor Know How Much Electricity Is Needed Wally W. <ww84wa@aim.com> - 2016-04-26 22:58 -0400
        Re: How Does an Electric Motor Know How Much Electricity Is Needed Sylvia Else <sylvia@not.at.this.address> - 2016-04-27 13:14 +1000
          Re: How Does an Electric Motor Know How Much Electricity Is Needed Wally W. <ww84wa@aim.com> - 2016-04-26 23:32 -0400
            Re: How Does an Electric Motor Know How Much Electricity Is Needed Sylvia Else <sylvia@not.at.this.address> - 2016-04-27 13:49 +1000
              Re: How Does an Electric Motor Know How Much Electricity Is Needed Wally W. <ww84wa@aim.com> - 2016-04-26 23:53 -0400
                Re: How Does an Electric Motor Know How Much Electricity Is Needed Wally W. <ww84wa@aim.com> - 2016-04-27 00:06 -0400
              Re: How Does an Electric Motor Know How Much Electricity Is Needed benj <nobodyxx@gmail> - 2016-04-27 01:25 -0400
                Re: How Does an Electric Motor Know How Much Electricity Is Needed Sylvia Else <sylvia@not.at.this.address> - 2016-04-27 15:41 +1000
                  Re: How Does an Electric Motor Know How Much Electricity Is Needed Wally W. <ww84wa@aim.com> - 2016-04-27 07:06 -0400
                    Re: How Does an Electric Motor Know How Much Electricity Is Needed edprochak@gmail.com - 2016-04-27 05:31 -0700
                      Re: How Does an Electric Motor Know How Much Electricity Is Needed Wally W. <ww84wa@aim.com> - 2016-04-27 09:21 -0400
                        Re: How Does an Electric Motor Know How Much Electricity Is Needed edprochak@gmail.com - 2016-04-27 11:06 -0700
                  Re: How Does an Electric Motor Know How Much Electricity Is Needed benj <nobodyxx@gmail> - 2016-04-27 11:22 -0400
                    Re: How Does an Electric Motor Know How Much Electricity Is Needed jimp@specsol.spam.sux.com - 2016-04-27 16:44 +0000
                  Re: How Does an Electric Motor Know How Much Electricity Is Needed "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-04-27 11:35 -0700
                    Re: How Does an Electric Motor Know How Much Electricity Is Needed benj <nobodyxx@gmail> - 2016-04-27 18:44 -0400
                      Re: How Does an Electric Motor Know How Much Electricity Is Needed Wally W. <ww84wa@aim.com> - 2016-04-27 22:16 -0400
                        Re: How Does an Electric Motor Know How Much Electricity Is Needed benj <nobodyxx@gmail> - 2016-04-27 23:09 -0400
        Re: How Does an Electric Motor Know How Much Electricity Is Needed benj <nobodyxx@gmail> - 2016-04-26 23:34 -0400
    Re: How Does an Electric Motor Know How Much Electricity Is Needed "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-04-27 11:44 -0700
      Re: How Does an Electric Motor Know How Much Electricity Is Needed Sam Wormley <swormley1@gmail.com> - 2016-04-27 15:45 -0500
        Re: How Does an Electric Motor Know How Much Electricity Is Needed Sergio <invalid@invalid.com> - 2016-04-27 22:30 -0500
          Re: How Does an Electric Motor Know How Much Electricity Is Needed benj <nobodyxx@gmail> - 2016-04-28 00:38 -0400
      Re: How Does an Electric Motor Know How Much Electricity Is Needed benj <nobodyxx@gmail> - 2016-04-27 18:43 -0400
    Re: How Does an Electric Motor Know How Much Electricity Is Needed gyansorova@gmail.com - 2016-04-27 11:58 -0700

Page 3 of 3 — ← Prev page 1 2 [3]

#573845

On Wed, 27 Apr 2016 18:44:32 -0400, benj wrote:

>On 04/27/2016 02:35 PM, reber g=emc^2 wrote:
>> On Tuesday, April 26, 2016 at 10:41:16 PM UTC-7, Sylvia Else wrote:
>>> On 27/04/2016 3:25 PM, benj wrote:
>>>> On 04/26/2016 11:49 PM, Sylvia Else wrote:
>>>>> On 27/04/2016 1:32 PM, Wally W. wrote:
>>>>>> On Wed, 27 Apr 2016 13:14:03 +1000, Sylvia Else wrote:
>>>>>>
>>>>>>> On 27/04/2016 12:58 PM, Wally W. wrote:
>>>>>>>> On Wed, 27 Apr 2016 11:33:17 +1000, Sylvia Else wrote:
>>>>>>>>
>>>>>>>>> On 25/04/2016 2:39 AM, reber g=emc^2 wrote:
>>>>>>>>>> It even pulls in more electrons when doing moire work
>>>>>>>>>> automatically.WOW  I can see why the thickness of a wire obeys the
>>>>>>>>>> inverse square law.  I love electric motors,and I'm big on electron
>>>>>>>>>> flow. Trebert
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> With increasing load, it slows down. As it does, the current has to
>>>>>>>>> increase so that the back EMF at the reduced speed still equals the
>>>>>>>>> applied voltage.
>>>>>>>>
>>>>>>>> It's all describable, but it is still akin to magic.
>>>>>>>
>>>>>>> It doesn't seem akin to magic to me.
>>>>>>>
>>>>>>> Sylvia.
>>>>>>
>>>>>> Lessee ... the generator in the next town knows just how many
>>>>>> electrons it should send to my motor.
>>>>>
>>>>> Of course it doesn't. The electrons in the wire respond to the local
>>>>> voltage gradient in the wire. Increasing the load on your motor slows it
>>>>> down, and the reduced back EMF increases the voltage gradient at the
>>>>> input to the motor. So more electrons at that point. That changes the
>>>>> voltage gradient a bit upstream, and more electrons flow there. The
>>>>> change propagates along the wire, at a good fraction of the speed of
>>>>> light, until it eventually reaches the generator, which responds
>>>>> accordingly.
>>>>>
>>>>> With an AC system, everything's cycling 50 or 60 times a second anyway,
>>>>> and the effect of the motor load is superimposed on that.
>>>>>
>>>>> Sylvia.
>>>>
>>>> Nice theory Sylvia, but generally speaking motors don't slow down when
>>>> delivering power. So how does your theory work with synchronous motors?
>>>
>>> In a synchronous motor, the current and the power factor, are a function
>>> of the angle between the rotor and the rotating field. When you load a
>>> synchronous motor there is indeed a temporary reduction in speed while
>>> the angle increases, which leads to an increase in current and power
>>> factor. The increased current, coupled with the angle, cause in increase
>>> in torque, which prevents further increase in the angle, and the speed
>>> returns to what it was originally.
>>>
>>> Again, nothing magical, just a straight forward application of
>>> electromagnetism.
>>>
>>> Sylvia.
>>
>> Sylvia You have it mostly right.Leave out the rotor slowing down.It can be made to slow down by overloading it with work.That will cause it to start to smoke,and burn up the amature in short time.  Trebert
>>
>Sylvia, treeb knows how everything works. You had better listen to him 
>or you'll get smoke! Imperial thought.

https://www.reddit.com/r/videos/comments/3vfxb8/louis_ck_describes_working_on_an_awards_show_with/cxoe2ju
It's a little known fact that electric motors run on smoke, let the
smoke out and they won't work anymore.

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#573856

On 04/27/2016 10:16 PM, Wally W. wrote:
> On Wed, 27 Apr 2016 18:44:32 -0400, benj wrote:
>
>> On 04/27/2016 02:35 PM, reber g=emc^2 wrote:
>>> On Tuesday, April 26, 2016 at 10:41:16 PM UTC-7, Sylvia Else wrote:
>>>> On 27/04/2016 3:25 PM, benj wrote:
>>>>> On 04/26/2016 11:49 PM, Sylvia Else wrote:
>>>>>> On 27/04/2016 1:32 PM, Wally W. wrote:
>>>>>>> On Wed, 27 Apr 2016 13:14:03 +1000, Sylvia Else wrote:
>>>>>>>
>>>>>>>> On 27/04/2016 12:58 PM, Wally W. wrote:
>>>>>>>>> On Wed, 27 Apr 2016 11:33:17 +1000, Sylvia Else wrote:
>>>>>>>>>
>>>>>>>>>> On 25/04/2016 2:39 AM, reber g=emc^2 wrote:
>>>>>>>>>>> It even pulls in more electrons when doing moire work
>>>>>>>>>>> automatically.WOW  I can see why the thickness of a wire obeys the
>>>>>>>>>>> inverse square law.  I love electric motors,and I'm big on electron
>>>>>>>>>>> flow. Trebert
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> With increasing load, it slows down. As it does, the current has to
>>>>>>>>>> increase so that the back EMF at the reduced speed still equals the
>>>>>>>>>> applied voltage.
>>>>>>>>>
>>>>>>>>> It's all describable, but it is still akin to magic.
>>>>>>>>
>>>>>>>> It doesn't seem akin to magic to me.
>>>>>>>>
>>>>>>>> Sylvia.
>>>>>>>
>>>>>>> Lessee ... the generator in the next town knows just how many
>>>>>>> electrons it should send to my motor.
>>>>>>
>>>>>> Of course it doesn't. The electrons in the wire respond to the local
>>>>>> voltage gradient in the wire. Increasing the load on your motor slows it
>>>>>> down, and the reduced back EMF increases the voltage gradient at the
>>>>>> input to the motor. So more electrons at that point. That changes the
>>>>>> voltage gradient a bit upstream, and more electrons flow there. The
>>>>>> change propagates along the wire, at a good fraction of the speed of
>>>>>> light, until it eventually reaches the generator, which responds
>>>>>> accordingly.
>>>>>>
>>>>>> With an AC system, everything's cycling 50 or 60 times a second anyway,
>>>>>> and the effect of the motor load is superimposed on that.
>>>>>>
>>>>>> Sylvia.
>>>>>
>>>>> Nice theory Sylvia, but generally speaking motors don't slow down when
>>>>> delivering power. So how does your theory work with synchronous motors?
>>>>
>>>> In a synchronous motor, the current and the power factor, are a function
>>>> of the angle between the rotor and the rotating field. When you load a
>>>> synchronous motor there is indeed a temporary reduction in speed while
>>>> the angle increases, which leads to an increase in current and power
>>>> factor. The increased current, coupled with the angle, cause in increase
>>>> in torque, which prevents further increase in the angle, and the speed
>>>> returns to what it was originally.
>>>>
>>>> Again, nothing magical, just a straight forward application of
>>>> electromagnetism.
>>>>
>>>> Sylvia.
>>>
>>> Sylvia You have it mostly right.Leave out the rotor slowing down.It can be made to slow down by overloading it with work.That will cause it to start to smoke,and burn up the amature in short time.  Trebert
>>>
>> Sylvia, treeb knows how everything works. You had better listen to him
>> or you'll get smoke! Imperial thought.
>
> https://www.reddit.com/r/videos/comments/3vfxb8/louis_ck_describes_working_on_an_awards_show_with/cxoe2ju
> It's a little known fact that electric motors run on smoke, let the
> smoke out and they won't work anymore.
>
Absolutely true fizics. This winter while it was still cold, my furnace 
blower motor let the smoke out and would you know it, it quit working!

Had to put a new motor in there.  I witnessed this science myself.

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#573619

On 04/26/2016 10:58 PM, Wally W. wrote:
> On Wed, 27 Apr 2016 11:33:17 +1000, Sylvia Else wrote:
>
>> On 25/04/2016 2:39 AM, reber g=emc^2 wrote:
>>> It even pulls in more electrons when doing moire work
>>> automatically.WOW  I can see why the thickness of a wire obeys the
>>> inverse square law.  I love electric motors,and I'm big on electron
>>> flow. Trebert
>>>
>>
>> With increasing load, it slows down. As it does, the current has to
>> increase so that the back EMF at the reduced speed still equals the
>> applied voltage.
>
> It's all describable, but it is still akin to magic. Stop the shaft,
> and the current will increase to burn up the windings. Let the shaft
> turn freely, and current will be just enough to both create and come
> to equillibrium with an induced magnetic field; plus overcome
> frictions of various kinds, temperature-varying resistive losses, etc.
>
> And, supposedly, the Big Bang did it.
>
Motors are just smart and they are pals with the electric wires and so 
tell them exactly what they need! Herb knows how everything works.

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#573762

On Sunday, April 24, 2016 at 9:39:43 AM UTC-7, reber g=emc^2 wrote:
> It even pulls in more electrons when doing moire work automatically.WOW  I can see why the thickness of a wire obeys the inverse square law.  I love electric motors,and I'm big on electron flow. Trebert

A Generator and electric motor relate so well.  Like left and right. Like transformer and reciever.Like black and white.etc. Trebert

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#573787

On 4/27/16 1:44 PM, reber g=emc^2 wrote:
> A Generator and electric motor relate so well.  Like left and right. Like transformer and reciever.Like black and white.etc. Trebert


   Like salt and pepper.



-- 

sci.physics is an unmoderated newsgroup dedicated
to the discussion of physics, news from the physics
community, and physics-related social issues.

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#573860

On 4/27/2016 3:45 PM, Sam Wormley wrote:
> On 4/27/16 1:44 PM, reber g=emc^2 wrote:
>> A Generator and electric motor relate so well.  Like left and right.
>> Like transformer and reciever.Like black and white.etc. Trebert
>
>
>    Like salt and pepper.
>
>
>

like motor/generator


     like Rotor-Stator



        and Tesla dreamed it, the created it, powering the world

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#573868

On 04/27/2016 11:30 PM, Sergio wrote:
> On 4/27/2016 3:45 PM, Sam Wormley wrote:
>> On 4/27/16 1:44 PM, reber g=emc^2 wrote:
>>> A Generator and electric motor relate so well.  Like left and right.
>>> Like transformer and reciever.Like black and white.etc. Trebert
>>
>>
>>    Like salt and pepper.
>>
>>
>>
>
> like motor/generator
>
>
>      like Rotor-Stator
>
>
>
>         and Tesla dreamed it, the created it, powering the world

Nah, Tesla stole motors from some Italian guy. Tesla was just an Edison 
technician and he had sex with birds. Probably because The Bird's the 
Word. At least that's what HVAC told me.

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#573814

On 04/27/2016 02:44 PM, reber g=emc^2 wrote:
> On Sunday, April 24, 2016 at 9:39:43 AM UTC-7, reber g=emc^2 wrote:
>> It even pulls in more electrons when doing moire work automatically.WOW  I can see why the thickness of a wire obeys the inverse square law.  I love electric motors,and I'm big on electron flow. Trebert
>
> A Generator and electric motor relate so well.  Like left and right. Like transformer and reciever.Like black and white.etc. Trebert
>
Like gravity and inertia! Both two sides of the same coin! That is a 
given, Reber.

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#573764

On Monday, April 25, 2016 at 4:39:43 AM UTC+12, reber g=emc^2 wrote:
> It even pulls in more electrons when doing moire work automatically.WOW  I can see why the thickness of a wire obeys the inverse square law.  I love electric motors,and I'm big on electron flow. Trebert


Not a stupid question as such. forget inverse square laws - that's sound and wireless. let an engineer answer your question.

You design a motor to handle a particular maximum load. When you load the motor the current will increase. This is because the load torque increases and current is proportional to torque. It is simply Ohms law and nothing else. forget motors however, suppose you have an ordinary 20W light bulb and you replace it with a 100W one. To deliver more power there must be more voltage or more current. If the voltage remains the same (which it must in a house) the current goes up. I=P/V.  Now back to motors. If you want the motor to keep the same speed when you load it you must put feedback around it and this adjusts the voltage applied to the motor (for a dc motor at least).

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