I believe it is a transorb or MOV.  Either way, it is a surge supressor.  It
is likely just after the input fuse and in parallel accross the AC input.
Sometimes after repeated surges they permanently short.  Most likely you
don't have a problem down the line that caused the problem.

Brian Kraut
Engineering Alternatives, Inc.
www.engalt.com

-----Original Message-----
From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu]On Behalf
Of Brooke Clarke
Sent: Tuesday, January 22, 2008 1:57 PM
To: piclist@mit.edu
Subject: [EE] Dead Mystery Component


Hi:

A computer monitor stopped working and had that smell.  After getting it
apart
enough to have a look found this circular component cracked almost into two
parts and the PCB is charred on one leg.  It's at the line input section of
the
mains power supply right next to a bridge rectifier and large filter cap.
On
the pcb below the part is what looks like a schematic symbol in the form of
a
"Z".  Photo at:   http://www.prc68.com/I/HaT.shtml#CM

What is it?  Do they fail, or is it likely something down stream is shorted?

--
Have Fun,

Brooke Clarke
http://www.prc68.com/Alpha.shtml  All my web pages listed based on html name
http://www.PRC68.com
http://www.precisionclock.com
http://www.prc68.com/I/WebCam2.shtml 24/7 Sky-Weather-Astronomy Web Cam
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