Delta C2000 Series User Manual page 670

3. Common-mode noise is coupled via the power cable to other power systems then the cable of such a
power system is coupled to the transmission system, as shown in Figure 3.
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 4.
5. When excessive pulse modulated currents pass through an un-grounded AC drive cable, it acts as an
antenna and creates radiated interference.
3