RKL4429 by Bosch Rexroth Indramat

The RKL4429 is a motor power cable produced by Bosch Rexroth Indramat and belongs to the RKL Motor Power Cables series. Designed for servo axes that move along linear guides or robotics, the cable routes both power and low-voltage control lines to a motor while tolerating continuous flexing inside an energy chain. Its role in industrial automation is to maintain reliable electrical connectivity between a stationary drive controller and a traveling motor without compromising mechanical life or signal integrity.

This cable has an outside diameter of 25.5 mm, so drag-chain slot planning is straightforward. In fixed installation, the minimum bend radius is 5 × D. Under dynamic motion, the minimum bend radius is 7.5 × D, which helps keep conductor stress below fatigue thresholds. The four power cores each have a cross-section of 16.0 mm², combined with auxiliary pairs wired as 2×1.5 mm² in the 4x16.0 + 2x(2x1.5) StC configuration. Copper resistance is 1.21 ?/km, allowing low voltage drop over typical machine lengths. The PUR outer jacket is adhesion-free and matte, finished in RAL 2003 orange to remain visible inside machinery, and it supports use in energy chains through a compound chosen for abrasion resistance and oil tolerance.

The cable is rated for 5,000,000 flex cycles, so it can accompany high-speed gantries through long operating periods. Capacitance between cores is held to 1.2 nF/m, which helps the connected drive maintain EMC performance during rapid PWM switching. In fixed installation, the conductors may reach 90 °C without degradation, and the power cores are insulated for up to 300/500 V while the integral control pairs operate at 300/300 V. The halogen-free design minimizes toxic emissions during a fire, and the jacket resists tearing even after prolonged exposure to lubricants.