RKL4477 by Bosch Rexroth Indramat

The RKL4477 cable is supplied by Bosch Rexroth Indramat as part of the RKL Motor Power Cables series. It is a flexible power and feedback link intended for servo axes that operate inside energy-chain assemblies or robotics. Within an automation cell, the cable transfers three-phase motor power along with auxiliary control signals while tolerating constant motion, so it serves as the dedicated interconnect between the drive amplifier and the moving motor housing. This arrangement lets one cable route motor energy and related control functions through the same moving path without adding separate loose wiring.

Electrical performance starts with a conductor resistance of 0.386 ?/km, which restricts voltage drop and heating over extended drag-chain lengths. This low resistance keeps I²R losses minimal during peak torque events and helps maintain stable motor supply under changing load. The cable diameter of 36.8 mm provides the necessary bend radius margin while fitting common guide-tray dimensions. Its outer sheath is composed of PUR (adhesion-free, matte), a material that resists cutting oils and avoids sticking to adjacent cables during continuous flexing. The power cores are insulated for up to 600 V AC, allowing direct connection to standard servo inverters, and the separate control pair insulation supports 300 V AC, which helps reduce crosstalk between power and signal paths during high-current surges.

The cable core layout includes 4x2.5 mm² control conductors that can carry brake release or temperature sensor circuits alongside the three power phases. A distributed capacitance of 1.3 nF/m is low enough to limit reactive current, supporting precise PWM edge control in the drive. During installation in gantry or pick-and-place modules, the assembly withstands linear speeds up to 5 m/s and can handle accelerations of 10 m/s². Those motion limits suit cable carriers that reverse direction frequently, where repeated bending and rapid travel place continuous stress on the jacket and conductor bundle.