Re: SRSG motor power

["Gomez ADDams" <gomez-at-netherworld-dot-com> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

on that fateful day 7/29/00 4:33 PM, Tesla list uttered:

> Hey Gomez, how's things?

Cramped, but at least I now have a 2 car garage with ample power to work in,
as opposed to the previous one car with no power!

I am sorry I probably won't see your coil at the SRL show in Phoenix, unless
I can figure out a miracle.  As luck would have it, I'm part of a team
competing in the 2nd Annual Colorado Pumpkin Launch on the same day.

Don't know if you plan to attend Burning Man again, but I won't be there
either.

OK, back to business:
> One important point to remember about wind loading on rotating
> armatures is that the required power increases with the *cube*
> of the speed.

It is fortunate then, that I'm planing to run at 1800 rpm rather than 3600!

> My "guess" on your application would be about 1 to 1.5 HP at
> 3600 RPM... perhaps 10% to 20% less with good shrouding.

I've already got the rotor and stators built, and I don't see an easy way to
add shrouding after the fact.  But it may be unnecessary.
 
> I'm not sure what starting torque you should expect, as I ramp
> both of my RSG's in a controlled current fashion.

I may add a soft-start motor controller, if it seems like the motor needs
it.

> But typically 
> for a motor starting something like a pump, the start currents
> can be 5 to 10 times the running current, for several seconds.

Certainly, the locked rotor current is typically 600% of full load motor
current.

- Gomez / Bill / Arkoff

........................................................................
this message was made possible by: Bill Lemieux, Gomez A.D.D.ams, Arkoff
Kapacitor, The Mad Scientists Club, The Denver Area Science Fiction
Association, The National Security Agency, The Defense Advanced Research
Projects Agency, the letter 'Q', and the number '7'.