Re: [CAD_CAM_EDM_DRO] Re: More on Re: Insulating D-shell from chassis?

zephyrus@... wrote:

>At 12:27 AM 11/19/03 -0600, Jon wrote:
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>>I would make a first guess that the spindle drive is conducting EMI onto
>>
>>
>the
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>>power line. If you can come up with an interference isolator (often used
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>as
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>>part of a power input module on high-end computer and instrument gear)
>>and put it in the line to the spindle drive, i bet it will clean up the
>>problem.
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>Yes, I have a number of inlet filters and tried them on the spindle, driver
>box and PC singly and in combinations, and that did nothing to improve the
>problem.
>
>

In that case, I suspect the motor is conducting noise to the machine frame,
which is then conducting it back to the drivers. I wonder if the spindle
motor has capacitors to shunt noise to the motor frame. You might want
to try removing these if accessible, or isolating the spindle motor from
the machine frame. (Yup, that has safety concerns, too.)

Jon