In message <[email protected]>, dated Thu,
6 Dec 2012, Brian Oconnell <[email protected]> writes:
The CPSC has issued a re-call for this "Dual-Voltage" unit for causing
fires at 220V <www.cpsc.gov/cpscpub/prerel/prhtml13/13022.html>. But
the rating label indicates an input rating of '100-240'. Also looks
like the unit is Class II construction, and that each component is
individually powered. Label image here
<http://www.cpsc.gov/cpscpub/prerel/prhtml13/13022d.jpg>
complete notice here
<www.cpsc.gov/cpscpub/prerel/prhtml13/13022.html>
Would love to see the root-cause analysis.
There aren't many things these days that are likely to cause a fire in
an audio unit. It's the subwoofer that burns up, and perhaps the most
likely thing to burn is the cone of the driver; maybe the sound
absorbent filling contributes.
Diver cone fires have been known in the past, caused by audio amplifier
output stage device(s) failing, passing DC through the driver
voice-coil. Separate amplifiers now have protection against this, but it
might be left out of a powered subwoofer.
Of course, this is pure speculation.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
The longer it takes to make a point, the more obtuse it proves to be.
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK
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