EN / ACS800-31/U31 Hardware Manual - Simark Controls

51Selecting the power cablesGeneral rulesDimension the mains (input power) and motor cables according to localregulations:• The cable must be able to carry the drive load current. See chapter Technicaldata for the rated currents.• The cable must be rated for at least 70 °C maximum permissible temperature ofconductor in continuous use. For US, see Additional US requirements.• The inductance and impedance of the PE conductor/cable (grounding wire) mustbe rated according to permissible touch voltage appearing under fault conditions(so that the fault point voltage will not rise excessively when a ground faultoccurs).• 600 VAC cable is accepted for up to 500 VAC. 750 VAC cable is accepted for upto 600 VAC. For 690 VAC rated equipment, the rated voltage between theconductors of the cable should be at least 1 kV.For drive frame size R5 and larger, or motors larger than 30 kW (40 HP),symmetrical shielded motor cable must be used (figure below). A four-conductorsystem can be used up to frame size R4 with up to 30 kW (40 HP) motors, butshielded symmetrical motor cable is recommended.Note: When continuous conduit is employed, shielded cable is not required.A four-conductor system is allowed for input cabling, but shielded symmetrical cableis recommended. To operate as a protective conductor, the shield conductivity mustbe as follows when the protective conductor is made of the same metal as the phaseconductors:Cross-sectional area of the phaseconductorsS (mm 2 )Minimum cross-sectional area of thecorresponding protective conductorS p (mm 2 )S < 16S16 < S < 35 1635 < S S/2Compared to a four-conductor system, the use of symmetrical shielded cablereduces electromagnetic emission of the whole drive system as well as motorbearing currents and wear.The motor cable and its PE pigtail (twisted shield) should be kept as short aspossible in order to reduce electromagnetic emission.Planning the electrical installation