RKL4415 by Bosch Rexroth Indramat

The RKL4415 is a motor power cable manufactured by Bosch Rexroth Indramat within the RKL Motor Power Cables series. It serves as the fixed or trailing connection between a servo drive and its motor, carrying three-phase power along with auxiliary control conductors so that automated axes can be energized and monitored without separate wiring systems. By combining motor phases and auxiliary conductors in one assembly, it reduces the number of separate cable runs between the control cabinet and the axis.

The conductor bundle is arranged as 4x16 mm² + 2x(2x1.5 mm²), supplying the main phases while leaving two shielded pairs available for temperature sensors or brake circuits. A design limit of 600 V AC matches the voltage class of many Rexroth inverters. The copper path has a resistance of 1.21 Ohm/km at 20 °C, which helps reduce voltage drop on long runs. The cable has an overall diameter of 25.5 mm, which affects gland selection and routing space inside drag chains. For stationary placement, the minimum bending radius is 5 x D, which helps protect the internal insulation during tight cabinet bends. When the cable moves, a larger 7.5 x D radius is required to reduce strand fatigue. Core-to-core capacitance is limited to 1.2 nF/m, which helps reduce capacitive inrush when the drive is switched on.

An outer sheath of PUR resists oil, abrasion, and welding sparks, and it is colored RAL 2003 for clear identification of power circuits. In continuous-motion applications, the flexible-state conductor temperature limit is 80 °C under dynamic load. For fixed installation, the conductor temperature limit is 90 °C when the cable is clamped in place inside a control cabinet. These thermal limits and the larger bending radius used during motion help reduce insulation stress during repetitive cycles.