Eaton M-Max Series Operating Instructions Manual

Also see for MMX11 Series: Installation instructions User manual

Contents

04/10 MN04020001Z-EN Electrical Installation39Prevent the shielding from becoming unbraided, i.e. by pushingthe separated plastic covering over the end of the shielding or witha rubber grommet on the end of the shielding. As an alternative,in addition to a broad area cable clip, you can also twist theshielding braid at the end and connect to protective ground witha cable clip. To prevent EMC disturbance, this twisted shieldingconnection should be made as short as possible (see figure 32).Shielded, four-wire cable is recommended for the motor cables.The green-yellow line of this cable connects the protective groundconnections from the motor and the frequency inverter andtherefore minimizes the equalizing current loads on the shieldingbraid.Twisted shielding braid should be connected with a ring cableterminal (see figure 29, page 38) on PES.The following figure shows the construction of a four-wire,shielded motor line (recommended specifications).If there are additional subassemblies in a motor circuit (i.e. motorcontactors, relays, motor reactor, sinusoidal filters or terminals),interrupt the shielding of the motor cable in the vicinity of thesesubassemblies. Connect this over a broad surface area with themounting plate (PES). Free or non-shielded connection cablesshould not be any longer than about 300 mm.Figure 30: Connection in power sectionFigure 31: Screened connection cableFigure 32: Connection with twisted cable shieldingRecommended value for twisted cable shielding:b f 1/5 a8 mm(0.314“)20 mm(0.787“)8 mm(0.314“)35 mm(1.378“)PE L1 L2 L3PE U V W8 mm(0.314“)20 mm(0.787“)8 mm(0.314“)35 mm(1.378“)PE R+ R-150.59’’PESU/T1 V/T2 W/T3a bPESFigure 33: Four-core shielded motor supply cablea Cu shield braidb PVC outer sheathc Drain wire (copper strands)d PVC core insulation, 3 x black, 1 x green–yellowe Textile and PVC fillersbae d c