[TheForge] Electric forge blower

[Paul Sperbeck]

On 06/18/2011 05:20 PM, Lynn and Susan Lang wrote:
> Hello
> Not all motors with brushes are universal...and take kindly to speed
> control. You could find a motor with brushes and it could be a
> "repulsion start induction run motor". I would not put a speed control
> on it.
> lynn
>
I made no inference that all motors with brushes were universal.
I referenced AC/DC Universal motors, which are a specific type of motor.
please see:
http://en.wikipedia.org/wiki/Electric_motor
scroll about half way into the wiki page and you will find Universal Motors

The problem of speed control has been exacerbated by a number of 
suppliers over the years who did not understand how speed is controlled 
in electric motors, and sold controllers that 'worked... sort of' but 
were technically flawed and just wrong.

If you do not want to control the speed of an AC motor with a variable 
frequency drive, or use a speed controllable DC motor in the first 
place, you would be better off just using an air gate on the inlet or 
the outlet of the blower. As long as the motor that you use in a 
synchronous ac motor it will not over-speed as the load is reduced by 
choking off the air intake.

-- 
Paul
WB9HCO
My Grandfather WAS a blacksmith...
and it didn't do me one damn bit of good.
All opinions are the personal beliefs of the author, and are based on
decades of experience... so use your best judgment, I'm just a lowly
craftsman.
   "The difference between genius and stupidity is that genius has its
limits." -Albert Einstein
"Life is hard...it's harder if you're stupid" John Wayne - Sands of Iwo
Jima