RKL4316 by Bosch Rexroth Indramat

The RKL4316 is a flexible motor power cable from Bosch Rexroth Indramat in the RKL Motor Power Cables series. It connects IndraDrive servo amplifiers to synchronous motors, carrying three-phase power, protective earth, and auxiliary sensor lines inside one sheath. Within automated handling, gantry, and pick-and-place axes, the cable supplies continuous current while enduring rapid motion inside energy-chain systems. Keeping the power and auxiliary lines together reduces the need for separate moving cable runs along the axis. The combined cable design is useful where space in the energy chain is limited and cable management must remain straightforward.

The cable endures 5 million bending cycles, enabling long service life in continuous-flex tracks. A dynamic bending radius of 7.5 × D keeps the copper conductors within elastic limits during travel. Axis motion can reach accelerations of 10 m/s² and linear speeds of 5 m/s without interrupting power delivery. With an outer diameter of 17.0 mm, the assembly fits common drag-chain separators while leaving space between adjacent cables. Inside the jacket, three power cores, a dedicated protective earth conductor, and two paired control circuits support motor supply, brake release, and temperature monitoring in one moving cable.

A conductor resistance of 4.95 ohms/km helps limit voltage drop along extended strokes. The outer sheath is PUR (adhesion-free, matte), which resists oils and weld spatter and helps prevent sticking during motion. Power delivery uses 3 x 4.0 mm² + PE 4.0 mm² copper conductors, while the smaller paired wires carry auxiliary functions. When the axis is parked, a static bending radius of 5 × D allows tighter routing through cabinet entries without overstressing the insulation. Termination is factory-crimped, with an angled motor connector on one end and a straight plug on the other for direct connection between the motor and drive. This arrangement supports clean routing from the cabinet to the motor on servo axes that reverse frequently during normal machine cycles.