Planning the electrical installation52Alternative power cable typesPower cable types that can be used with the drive are represented below.Motor cable shieldTo effectively suppress radiated and conducted radio-frequency emissions, theshield conductivity must be at least 1/10 of the phase conductor conductivity. Therequirements are easily met with a copper or aluminium shield. The minimumrequirement of the motor cable shield of the drive is shown below. It consists of aconcentric layer of copper wires with an open helix of copper tape. The better andtighter the shield, the lower the emission level and bearing currents.Symmetrical shielded cable: three phase conductorsand a concentric or otherwise symmetricallyconstructed PE conductor, and a shieldRecommendedPE conductorand shield Shield ShieldA separate PE conductor is required if the conductivityof the cable shield is < 50 % of the conductivity of thephase conductor.A four-conductor system:three phase conductorsand a protectiveconductorShieldPEPEPENot allowed for motor cables with phaseconductor cross section larger than 10 mm2[motors > 30 kW (40 HP)].Not allowed for motor cablesInsulation jacket Copper wire screen Helix of copper tapeCable coreInner insulationPhone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: info@clrwtr.com
