RKL4503 by Bosch Rexroth Indramat

The RKL4503 cable is produced by Bosch Rexroth Indramat within the RKL Motor Power Cables series. It is a multi-core assembly that delivers three-phase power and auxiliary control signals from a drive to a servo motor in automated machinery. The design supports coordinated motion axes, packaging lines, and other dynamic equipment where compact, flexible power cabling is required. Its flexible construction is suited to moving axes that require motor power and auxiliary connections in one cable.

The cable endures up to 5,000,000 bending cycles, so it can be routed through continuously moving drag chains without early fatigue. Its mutual conductor capacitance is typically 0.7 nF/m, which minimizes reactive current and helps maintain stable electrical behavior on longer runs. DC resistance of the copper cores is 7.98 ?/km at 20 °C, which helps limit voltage drop over the cable length. The cable includes 4 control conductors, each with a stranded cross-section of 1.0 mm², for auxiliary signals such as brake power. The stranded control conductors also help the cable tolerate repeated flexing in motion systems.

During motion, the bend radius must not fall below 7.5 × D, while fixed routing may tighten to 5 × D, which helps the cable fit compact cabinets and moving cable carriers. The overall diameter of 14.8 mm fits standard Rexroth cable clamps, and the three power cores each use a conductor area of 2.5 mm² plus a protective earth, matching typical drive output terminals up to 16 A. A PUR jacket with an adhesion-free, matte surface simplifies drag chain extraction and resists oil and coolant. The sheath is colored RAL 2003 orange for visibility in machine frames and common safety color coding. The protective earth conductor supports grounding continuity between the drive and motor housing.