Re: IS: Follow the Current - WAS: Apollo One, the FBI, and Scott Grissom

From: Derek Lyons (derekl1963_at_nospamyahoo.com)
Date: 06/07/04 

Date: Mon, 07 Jun 2004 18:42:17 GMT

hpywife927@yahoo.com (LaDonna Wyss) wrote:
>2. No upstream impedence. The switch was the source of the short;
>everything downstream was affected by the resultant voltage
>transients.

The problem is... While the behavior of other equipment on the bus
(the term downstream is incorrect) is consistent with voltage
transients , a hard short produces a standing change in voltage and
current flow, not transients. (If it's not a standing change, its by
definition not a hard short.) This standing change can be masked
however by the effects of switching other equipment on and off the
bus.

Parenthetically I find it hard to credit that a hard short in a
thruster switch would not cause the master breakers on the bus to
perform their intended functions and drop the bus entirely. (I don't
recall however if their were master breakers.)

Transients are indicative of 'arcing and sparking', which is
consistent with the known problems in the cabling inside the CM.
Transients are also a common condition when you have a variable short
or multiple variable shorts to ground (without arcing), again this is
consistent with the known problems with the cabling. Combine these
with the transient effects of switching on and off other equipment on
the bus and you can increase the effects of these cabling problems by
altering the current and voltage flow.

D. 

-- 
Touch-twice life. Eat. Drink. Laugh.

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