[BC] KOMO Fire

[Urban, Brian L]

I passed the pictures on to a friend who does forensic engineering.  He worked on a similar failure at a major sports venue in a major market.  His comments "... The failure in that one was in a 90 degree section of the incoming bus duct.  After taking the section to XXXX main facility, and the use of metallurgist, we determined the failure was due to water.  The water came from a sprinkler head above the area.  The sprinkler head failed and dumped water on it.

This failure in the article could have been caused by water or it could have been a loose connection.  To prevent the loose connection problem the use of infrared inspections every couple of years would be good.  Also, the bus duct should be correctly mounted and secured. ..."

He also suggested using dry pipe sprinklers in the electrical room.

--
Brian Urban
Chief Operator
KUT Radio
The University of Texas at Austin
TEL 512-471-1085

On 7/9/09 11:44 PM, "Dave Dunsmoor" <mrfixit at min.midco.net> wrote:

> It is bus duct, and is a sandwich of copper bus-bar and insulation,
encased in steel. The joints are held together by compression from a few
bolts, and the failure was at one of the corner joints.

    I see. I learn something new all the time (just gotta manage not to
forget all the useful stuff).

    I think it would be instructive to do an A/B comparison by fully loading
the bus (before the building is occupied) and make IR measurements, then
disassemble the joints, clean the copper, grease it with silver bearing
no-oxide, and redo the test.

Dave Dunsmoor