CDC 9766 Drive and packs

From: John Lawson <jpl15_at_netcom.com>
Date: Mon Feb 1 16:08:21 1999

On 1 Feb 1999, Eric Smith wrote:

> John Lawson <jpl15_at_netcom.com> wrote:
> > Is anyone on the List, in the Southern California area, interested in a

(snip)

>
> It NEEDS three-phase power, and a fair amount of it, to run the AC
> synchronous spindle motor. This is not something that can easily be
> converted to run on single-phase, so don't get the idea that you can
> run it in your house or garage. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^


    Ayyy! Sez 'oo?


  While single-to-three-phase converters are not normally household
items, they exist and are usefull for such endeavors. The ones in my
shop have the added bonus of being variable speed/torque/inrush ....
handy for starting up long-dormant machinery.

  But it is a trivial matter to run any three-pahse motor from
single phase... one uses capacitors to shift the phases of the
windings in proper relationship. It takes a knowledge of R/C
networks and a good AC ammeter to finely balance the currents in the
leads, but it can be done for the price of the caps. If one has
access to a large surplus or appliance salvage yard, so much the
better. I have run several machines this way.

  The drawbacks are: it's grossly inefficient
                     starting torque is low
                     careful 'tuning' is required for proper sync.



> But they are great drives, and it would be a shame for them to be scrapped.

  I'd rather not sell this one (though the offer was from a company
who maintains and re-builds them... so at least the cadaver would be
used to keep other drives alive) but it's taking up precious room
and it's *heavy*.

>
> Eric
>

 Thanks for the amplifying info... I did not know the RM05 was
mechanically similar.

  Cheerz

John
Received on Mon Feb 01 1999 - 16:08:21 GMT