21 Jan
2009
21 Jan
'09
8:57 a.m.
On Jan 21, 2009, at 8:40 AM, Paul Koning wrote:
Well you still need a lot of each. And finding -5.2v and -2v high
current regulators isn't *that* easy. The 12v DC supply in the KL-10
supplies 500A. I think each -5.2v regulator supplies 30A and there's
5-7 of them (if memory serves...I haven't looked at the power supplies
in my KL for a while). There's a similar number of -2v regulators but
slightly less current.
>>>> "Gordon" == Gordon JC Pearce MM3YEQ <gordonjcp at
gjcp.net> writes:
Gordon> Since extremely high current switchers are relatively cheap
Gordon> (at least compared to getting three-phase installed, and
Gordon> massive aircon systems), is there any reason why you
Gordon> *wouldn't* go down this route? Particularly for a machine
Gordon> that's going to be on a lot?
If you have an RP06 you need 3-phase anyway...
Note that you can generate 3 phase power from a 1 phase supply. There
are electronic devices to do this ("variable frequency converters",
devices intended to drive motors) up to 2 kW or so. Those can also
produce odd frequencies, so they might be a suitable substitute for a
CDC motor generator (for 400 Hz power). For higher power you can get
a "rotary phase converter" which is just a 3 phase motor with some
trick wiring. Those are more expensive though they are easy to build
from a suitable size surplus motor plus some capacitors.
One of the big problems in dealing with this is the in-rush current
which is *really* impressive. Go look at the KL10 installation manual
on the specs. It's a bit scary to have an in-rush current that high
(for up to 1-2 seconds). I don't know if those converters are set up
for those kinds of in-rush current. My understanding was they were
set up more for inductive loads (ie motors) but never having dealt
with them, I'm working from ignorance.
I just recall a friend who worked at KSC during Apollo where NASA had
something like a 2-4 ton flywheel to be power the critical launch
systems in the event of a power failure (to give time for the backup
generators to kick in). They'd launched several Apollo missions when
they decided to test a power failure during launch scenario
(simulated). His description was that there was the sound of a bomb
going off as the lights went out. Analysis afterwards indicated that
the flywheel stopped in about 1/4 of a revolution!
TTFN - Guy