[Stoves] Calculating the RPM

[Alex English]

Check out automationdirect.com
Alex
On 2013-02-13 12:25 AM, "David G. LeVine" <dlevine at speakeasy.net> wrote:

>  On 02/12/2013 01:30 PM, Frank Shields wrote:
>
> Building equipment for determining the hardness of pellets and biochar I
> need something to turn a 9 kg box at a speed of 60 RPM +/-  1.****
>
> I have a 1/3rd HP motor that is rated at 1725 RPM****
>
> Fitted with a 2” pulley attached to the motor and going to an 8” pulley
> gives me a shaft turning 431 RPM****
>
> Then another 2” pulley going to an 8” pulley on another shaft gives me 108
> RPM****
>
> I plan to adjust the 108 down to 60 using a voltage regulator. ****
>
> ** **
>
> ** **
>
> Is this a good plan? ****
>
> And is there another factor I need to include for the weight of the box I
> am turning?
>
>
> This is a BAD plan.
>
> Your motor is probably speed controlled by line frequency, not voltage.
> Cutting the voltage may or may not help, in fact, it can fry the motor if
> the centrifugal switch does not kick out.
>
> Get a 3 phase motor and a VFD and it will work well., but figure $100-$200
> MINIMUM for the VFD.  The 3 phase motor will be fairly cheap.
>
> Dave  8{)
> --
>
>
> *"Among the many misdeeds of British rule in India, history will look
> upon the Act of depriving a whole nation of arms as the blackest."*
>
> Mohandus Ghandi, An Autobiography, Page 446.
>
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