Love This

[Van Setten, Tim (AZ75)]

> Subject: 	Re: Love This
> 
> >  Could you, or someone, please explain PWM (assuming that PWM=Pulse
> Width
> Modulation) of cooling fans?
> 
> Subject: RE: Love This
> 
> >  Could you, or someone, please explain PWM (assuming that PWM=Pulse
> Width
> Modulation) of cooling fans?
> 
> Here's my .03 cents worth... Look at it from this angle.  The light dimmer
> is your house uses PWM to control the intensity of the light.  The reason
> the "brightness" of the light changes is because the "average power"
> dissipated changes, ie. 1/2 bright, 50/50 duty cycle, full bright, 100%
> duty cycle.
> 
> In an electric motor, the start currents etc. are very high, so PWM is
> used to overcome most of these losses.  Again, the reason the motor runs
> at 1/2 speed at 50/50 duty cycle is because the average power dissipated
> is 1/2 of full power.
> 
> Hope this helps....Tim.
>