Paul Skyrme:
Potentially if this is feeding a motor of a machine then BS 7671 is irrelevant. (110.2,xi)
If this is on a VSD, then the SWA will be probably useless as a screen.
Most we have tested are worse than un-screened.
Many drive OEM's forbid SWA to the motor for this very reason.
I'm interested by this. Are the tests comparing unscreened cable (with one core for earthing) with a similar length of SWA where both ends are bonded to metallic enclosures in the thorough way that Graham mentioned? What does the test measure? Do OEMs recommend e.g. a tightly-woven screen instead, to avoid the thin gaps between armour wires?
Paul Skyrme:
Potentially if this is feeding a motor of a machine then BS 7671 is irrelevant. (110.2,xi)
If this is on a VSD, then the SWA will be probably useless as a screen.
Most we have tested are worse than un-screened.
Many drive OEM's forbid SWA to the motor for this very reason.
I'm interested by this. Are the tests comparing unscreened cable (with one core for earthing) with a similar length of SWA where both ends are bonded to metallic enclosures in the thorough way that Graham mentioned? What does the test measure? Do OEMs recommend e.g. a tightly-woven screen instead, to avoid the thin gaps between armour wires?
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