RKL4523 by Bosch Rexroth Indramat

The RKL4523 is a motor power and control cable supplied by Bosch Rexroth Indramat and assigned to the RKL Motor Power Cables series. Built for integration between drive amplifiers and synchronous motors, it carries three-phase power plus auxiliary circuits required for brake release, temperature sensors, or encoder reference channels. By bundling these functions in one sheath, the cable simplifies routing inside machine beds and reduces panel space that would otherwise be used for separate conduits.

For physical layout planning, the cable's overall diameter is 18.5 mm, and its copper layout is 4x6.0+(2x1.0)StC+(2x1.5)StC mm², meaning four 6 mm² power cores along with two screened 1 mm² and two screened 1.5 mm² auxiliaries. When the assembly is clamped to static machine frames, the minimum bend arc is 5 × D. Moving drag-chain runs require 7.5 × D so that the conductor strands are not overstressed during every cycle. A loop resistance of 3.30 ohm/km at 20 °C limits voltage drop, so maximum feeder length can be calculated while maintaining the desired torque response. The geometry and resistance support continuous currents typical of medium-inertia axes without requiring a larger drive inverter.

The control cores are rated for 600 V AC, which matches the phase-power insulation level and allows the use of uniform termination hardware. Continuous conductor heat is tolerated up to +90 °C in fixed routing, while moving installations are limited to +80 °C to avoid insulation embrittlement. A PUR outer jacket with a matte, adhesion-free finish resists oils, cutting fluids, and UV exposure, so the assembly maintains dielectric strength after repeated clean-downs. This jacket also prevents sticking to adjacent cables, helping maintain consistent chain tracking and preserving the required bend radii during millions of flex cycles in energy chains.