[Info-vax] OT: the Daily WTF for today is a VAX/VMS story

[Scott Dorsey]

Jan-Erik Soderholm  <jan-erik.soderholm at telia.com> wrote:
>
>The wood work machinery in my grandfathes shipyard had 3-phase AC
>motors. It took several minutes to rev up some of them to speed.
>You put the switch first to the "Y" position and when the speed
>of the machinery was stable switched to "D". Seems to be called
>"star-delta (YΔ) starting" in English...

Yes.   That is how conventional induction motors spin up.  You'll
notice they pull a lot of current and get pretty hot until they come
up to speed and lock to the line. 

>So I do not understand this:
>
> > 3 phase AC motors always follows the phases of the supply like
> > slaves. There is no spinup time. You go from standstill to full
> > speed immediately, always.

It is not true, no.
--scott

-- 
"C'est un Nagra. C'est suisse, et tres, tres precis."