On Sun, 6 Sep 2009 01:39:33 -0500 (CDT), Christopher E. Brown wrote:
>Since every similar washer I checked was at least as bad, and mine only
>had motor controller noise I ordered a Corecom filter brick, 10amp, one
of
>the higher end units noted for use on VFD (Variable Frequency Drive)
>systems.
>I installed inside the washer case where the power cord enters, almost
>silent (90+ percent gone). Note, the filter *only* works when the filter
>body has a very good connection to the washer chassis, leave it floating
>and it makes no impact on the noise. I ground the paint off of the
inside
>of the chassis under the filter mounting tabs and used stainless hardware
>w/ no-ox grease to get a good connection, then removed that panel and
>cleaned up where the panel bonds to the base panel/frame (where motor
>controller and motor casings bolt to) to ensure a good connection.
>After that I could only hear it below 40 and it was weak, a 2.4in #31
>toroid on the power cable and I can no longer tell when it is running.
All very solid engineering techniques, and it sounds like a LOT of work.
The sad thing is that proper design of that motor control system for EMC
(most of which wouldn't cost much) would make it either un-necessary or
solvable with a lot less work.
73,
Jim Brown K9YC
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