Appendix A. EMC Standard Installation GuideVFD-ED
4. The common-mode noise of an unshielded power cable is transmitted to the ground via the stray
capacitance. Since both shielded wire and unshielded wire are connected to a common ground,
other systems can be interfered with by the common-mode noise that is transmitted from the
ground back to the system via the shield. See Figure A-4.
Noi se
Unshi el ded cabl e
Ground
Send
Recei ve
L oad
Cst r ay
Cst r ay
5. When excessive pulse modulated currents pass through an un-grounded AC drive cable, it acts as
an antenna and creates radiated interference.