From: "Tarver Engineering"
References: <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org> <3D9A879F.CF98EE43@citlink.net>
Subject: Re: (Avionics) How can this circuit produce an "inductive surge"?
Date: Thu, 3 Oct 2002 07:58:55 -0700
X-Newsreader: Microsoft Outlook Express 6.00.2600.0000
"Jim Pennino" wrote in message
> In rec.aviation.owning Peter Gottlieb wrote:
> > "Richard VanHouten" wrote in message
> > news:3D9A879F.CF98EE43@citlink.net...
> >> >
> >> > Why would you run a static inverter to make one frequency of AC then
> > a
> >> > MG set to convert to another frequency? Seems like a real kludge
> > me,
> >> > not to mention, a very noisy setup.
> >> >
> >> Well, if this is the product that my employer (then K/W Controls, Inc.,
> >> now Piller, Inc.) marketed, the static inverter was a standby unit, and
> >> the MG set ran off of mains except during a power failure. The 2
> >> ride-through of the MG set was plenty of time for the inverter to kick
> >> in, and your battery string would give you several minutes to shut down
> >> your computers, or let your diesel generator kick in if you had a
> >> premium setup.
> >> The frequency would drop a bit during the transfer, but IBM's spec said
> >> that was ok, as long as it stayed above (I think) 370 Hz.
> > Well, that makes some sense. But running a frequency converting MG set
> > a UPS is not an optimal solution - why not just make the UPS run at the
> > target frequency? The magnetics at 400 Hz are much lighter and
> > than those required for 60 Hz, and the higher frequency makes other
> > practical (eg, resonant).
> Even if you couldn't find a 400 Hz UPS (there are lots of sources for
> today), I would think the cost of converting a 60 Hz UPS would be a lot
> less than buying, installing, and running a MG set.
> And don't forget, "The output is also at 400 hz which makes the rectifiers
> in the computing equipment much smaller." HAR!!
For the same reason we use 400 cycle in aircraft.
I think Jimmy needs a nappy poo.