>From: "William Donzelli" <aw288_at_osfn.org>
>
>> Reminds me. The CDC Cyber 960 from http://www.cray-cyber.org/ runs at
>> 400 Hz. The higher frequency allows smaller transformers.
>
>I think the intent was to reduce the ripple, rather than reduce the
>weight. CDC wasn't afraid of a few more pounds.
>
>> The 400 Hz three phase current is generated by a motor-generator. The
>> rotating mass of this machine is enough to keep the Cyber running for
>> some seconds. (Power consumption of the Cyber at minimal configuration
>> is around 20 kW.) Enough to start a big diesel generator in case of a
>> power outage.
>
>I doubt you could start a big diesel that fast, reliably.
>
>The inertia would, however, protect against little dips and burps in the
>power, when the utilities are fooling around with the grid.
>
Hi William
I was right next to a flywheel started no-break diesel.
It was running at full load in about one second from
a complete stand still. My heart was pounding quite hard
from the adrenaline rush I got. Another way to start
a diesel fast is with compressed air.
In anycase, "Yes", they can start that fast.
Dwight
Received on Tue Dec 14 2004 - 18:08:40 GMT