Plug in shuttle

From http://news.bbc.co.uk/1/hi/sci/tech/6943451.stm

The mission is scheduled to last for 11 days but can be extended to 14
thanks to a new piece of equipment that allows the shuttle to tap into
the power grid of the ISS.

This is what we call a "plug".

I'm amazed this hasn't been done before. Both systems must be using
batteries somewhere in their systems so recharging must be pretty
straightforward. Even if their worried about vacuum welding
contactless charging devices are off the shelf items.

Is this an illustration of how EVERYTHING in space needs to be
reinvented, making it hugely expensive. Or is it an illustration of
the expensive way NASA chooses to do things.

Alex Terrell wrote in news:1186987878.631674.60830@
22g2000hsm.googlegroups.com:

From http://news.bbc.co.uk/1/hi/sci/tech/6943451.stm

The mission is scheduled to last for 11 days but can be extended to 14
thanks to a new piece of equipment that allows the shuttle to tap into
the power grid of the ISS.

Basically a voltage converter to drop the station voltage to the
Shuttle's 28 VDC bus; it's a set of 2 kilowatt inverters. The
Shuttle does not have any batteries to speak of, other than
the fuel cells which are also electrochemical devices just like
batteries.

Why hasn't it been done before? I dunno...maybe issues of
efficiency, reliability, weight and size reduction?

Station may not have had the extra power to spare until the
additional solar array was launched and put online. It may be
that the new array included batteries as well.

--Damon

Damon Hill wrote:
Alex Terrell wrote in news:1186987878.631674.60830@
22g2000hsm.googlegroups.com:

From http://news.bbc.co.uk/1/hi/sci/tech/6943451.stm

The mission is scheduled to last for 11 days but can be extended to 14
thanks to a new piece of equipment that allows the shuttle to tap into
the power grid of the ISS.

Basically a voltage converter to drop the station voltage to the
Shuttle's 28 VDC bus; it's a set of 2 kilowatt inverters. The
Shuttle does not have any batteries to speak of, other than
the fuel cells which are also electrochemical devices just like
batteries.

Why hasn't it been done before? I dunno...maybe issues of
efficiency, reliability, weight and size reduction?

Station may not have had the extra power to spare until the
additional solar array was launched and put online. It may be
that the new array included batteries as well.

--Damon

The Greenies will be happy that the shuttle is now partly solar powered.

Sylvia.

On Sun, 12 Aug 2007 23:51:18 -0700, Alex Terrell
wrote:


The mission is scheduled to last for 11 days but can be extended to 14
thanks to a new piece of equipment that allows the shuttle to tap into
the power grid of the ISS.

This is what we call a "plug".

I'm amazed this hasn't been done before.

The Station didn't have enough electrical power before. It achieved
that with the S4 solar arrays installed on the Atlantis flight in
June.

Brian

On Mon, 13 Aug 2007 18:18:28 +1000, Sylvia Else
wrote:

The Greenies will be happy that the shuttle is now partly solar powered.

The Greenies like that the Shuttle is hydrogen powered anyway. They
don't ask where they hydrogen comes from and no one tells them.

Brian

Alex Terrell wrote:
From http://news.bbc.co.uk/1/hi/sci/tech/6943451.stm

The mission is scheduled to last for 11 days but can be extended to 14
thanks to a new piece of equipment that allows the shuttle to tap into
the power grid of the ISS.

This is what we call a "plug".

The power bus -- er, sorry: grid -- of the ISS is not the same voltage as the
power bus of the shuttle. Thus, a (space rated) DC-DC converter needed to be
designed, built and qualified with both Station and Shuttle systems.

The qualifying of the device probably costs more than one device.

The plug has to be put somewhere... somewhere that it can be plugged in and
unplugged without requiring a space walk.

I'm amazed this hasn't been done before. Both systems must be using
batteries somewhere in their systems so recharging must be pretty

Shuttle has no batteries. Fuel Cells are a replacement for batteries.

Not all battieries are created equal. Some are 1.5v, some 6v, some 12v, some
48v. Some can be charged fast (e.g. flooded led-acid), some have to be chared
slow (e.g. gel cell), some are even more specialized (e.g. lithium ion). And
those are just the batteries that I own!


Glen Overby
Twin Cities, MN