RKL4509 by Bosch Rexroth Indramat

The RKL4509 is a motor power cable produced by Bosch Rexroth Indramat for the RKL Motor Power Cables series. It links servo drives to synchronous motors in automated machinery, carrying three-phase power and auxiliary control signals while withstanding continuous motion in cable tracks and robotic joints. By combining power conductors, signal pairs, overall shielding, and a protective PUR jacket in one assembly, the cable simplifies installation and maintains electromagnetic compatibility in industrial automation cells. This arrangement also reduces the need to route separate cable bundles through moving sections of a machine.

The overall cable diameter is 25.5 mm, a size that balances current-carrying capacity with flexibility for routing inside energy chains. Each power core has a cross-section of 4x16.0 mm², allowing low resistive losses during high current delivery to servo motors. Two twisted control pairs sized at 2x(2x1.5 mm²) run in the same sheath so brake or auxiliary circuits do not require a separate harness. When the cable is laid permanently, the minimum bending radius is 5 x D. Under dynamic motion, it should follow a larger radius of 7.5 x D. Observing these geometric limits helps reduce conductor fatigue and protects the internal shield from damage during repeated movement. The total shield also helps limit electrical noise near adjacent machine wiring.

Durability is quantified by a flex life of 5 million cycles, supporting long duty in high-speed gantries and other moving axes. Copper conductors may reach a continuous service temperature of 80°C without degrading the insulation system. The outer jacket is made from PUR, which provides abrasion resistance, hydrolysis resistance, and a matte, low-adhesion surface that is less likely to collect contaminants during operation. The jacket is colored Orange (RAL 2003) for quick identification on the factory floor. In addition, the formulation is halogen-free and silicone-free, and it uses a total shield to limit capacitive coupling into nearby signal cables. These material properties support reliable cable travel where repeated flexing, contact with coolants, and confined routing paths are common.