RKL4309 by Bosch Rexroth Indramat

The RKL4309 motor power cable is produced by Bosch Rexroth Indramat for the RKL Motor Power Cables series. It routes three-phase power and auxiliary control signals from a servo inverter to its matched motor on articulated robots, gantry axes, and linear stages. By integrating power cores and four screened control cores in one assembly, the cable simplifies installation while maintaining signal integrity in electrically noisy plant environments. It is intended for track-guided layouts where continuous cable motion is required.

The cable's mechanical life is rated for 5,000,000 bending cycles, indicating it can withstand repeated flexing without conductor fatigue during long-term machine operation. When laid permanently, the cable requires a minimum bend radius of 5 × D, which prevents compression of the insulation layers. During continuous motion, the radius may tighten only to 7.5 × D, a limit that guards against tensile stress on the copper strands. An overall diameter of 14.8 mm fits common cable tracks and provides creepage distance between power and signal pairs. The outer sheath uses a PUR (adhesion-free, matte) jacket that resists oil, coolant, and abrasive chips without sticking to adjacent surfaces.

Electrical terminations are simplified by factory-installed circular connectors: the motor-side interface RLS1201 mates with Rexroth synchronous motors, while the drive-side plug RLS0721 fits standard converter ports. Three conductors for phase power are dimensioned at a cross-section of 2.5 mm², giving sufficient ampacity for typical medium-frame servo units. The separate sensor and brake lines use control cores each sized at 1.0 mm², supporting encoder supply or holding-brake release without excessive voltage drop. All elements are color-coded under a RAL 2003 orange sheath, which improves visibility during panel service and aligns with international safety conventions.