RKL4540 by Bosch Rexroth Indramat

The RKL4540 motor power cable is manufactured by Bosch Rexroth Indramat as part of the RKL Motor Power Cables series. It links a drive controller to a servo motor in automated cells, carrying three-phase power along with auxiliary control cores through a single flexible jacket. The cable is designed for continuous motion in drag chains used on pick-and-place arms, gantry axes, and packaging machinery.

The cable endures 5 million bending cycles in an energy chain. Its layered build, labeled [4x16.0 mm² + 2x(2x1.5 mm²)StC]C, combines four power conductors and two shielded control pairs inside a common braid. Copper resistance of 1.21 ?/km at 20 °C limits voltage drop, while a discharge capacitance of 1.2 nF/m keeps drive-to-motor reactive currents low. Even with these cores, the outer diameter stays at 25.5 mm, allowing routing through compact cable trays. Each control pair retains a 1.5 mm² cross-section to match standard terminal blocks. A braided overall shield tied to the drive's PE terminal suppresses conducted and radiated EMI generated by fast-switching IGBTs.

The matte outer sheath uses PUR (adhesion-free, matte), which resists oil and welding debris and reduces surface drag between bundled leads. Inside, each power core is sized at 16.0 mm², providing sufficient ampacity without sacrificing flexibility. When permanently installed, the conductor temperature may reach 90 °C, while constant motion limits it to 80 °C to protect insulation life. The difference between those limits reflects the extra thermal stress created by repeated flexing in moving cable carriers. The smooth jacket also withstands abrasion from continuous contact with guide channels, preventing particulate buildup that could abrade adjacent signal cables.