On Jan 9, 2008, at 6:08 AM, R.S. wrote:
Paul Gilmartin wrote:
[...]
The phrase was "even for a second or two". The article makes it
pretty clear that the flywheels run all the time and there is zero
interruption.
Back to the future. Flywheels were in use in 60's. Not in IT, but
in industries, i.e. in yarn productions (synthetic fibres). long
before UPSes.
IMHO nowadays it is pointless. Modern diesel engines start in few
(i.e. 4) seconds. Those engines are heated constantly (using
electrical power). Flywheel is heavy, consumes energy, it wears,
last but not least: it is dangerous. In the old days it was mounted
in a bunker, rather underground.
For computer equipment there is no difference between 4 seconds and
0.5-1 second. UPS is a must for switching time.
R.S.
its been an interesting discussion. Thanks all for contributing. One
question remains in my mind though what is the allowable time power
maybe interrupted to a CPU ? 1 NS (nanosecond) ? or 0 NS? or ? As I
said in my original piece I am not familiar with UPS's and could some
one come up with a current answer? If the answer is it depends that
would be nice to know that, as well. Thanks.
Ed
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