RKL4551 by Bosch Rexroth Indramat

The Bosch Rexroth Indramat RKL4551 cable is a flexible motor power cable offered in the RKL Motor Power Cables series. Designed for dynamic routing between servo drives and motors, this cable supplies three-phase power and auxiliary signals in automated machinery. Its PUR jacket and mechanical construction target gantries, pick-and-place units, and other axes that experience continual motion. The pre-assembled layout reduces on-machine wiring work and keeps the power and auxiliary conductors bundled in one moving cable path.

The cable carries the motor main circuit through four 2.5 mm² copper cores and is rated for an operating voltage of 300/500 V, allowing connection to standard low-voltage inverters. Inside the round structure, a dedicated pair set identified as 2x(2x1.0 mm²) StC routes brake or sensor signals that are isolated from the power conductors. A finished outside diameter of 14.8 mm helps size cable chains and glands correctly. When installed in moving tracks, the design tolerates a dynamic bending radius of 7.5 × D. It also has a mechanical endurance of 5 million bending cycles, supporting repeated flexing in high-duty handling systems. The matte, adhesion-free PUR jacket and the specified static radius of 5 × D also help reduce stress at fixed anchor points.

The flexible element operates within an ambient range of -20 to +40 °C, so it remains pliable in unheated shops yet avoids softening near machinery heat. Bulk cable reference INK0602 confirms the same electrical geometry for custom-length assemblies. Factory-crimped terminations use Ferrules and Ring Terminal hardware on the motor side and a keyed RLS0722 Plug Connector toward the drive, reducing manual assembly steps and helping prevent wiring mistakes. Four 2.5 mm² power cores share the same PUR jacket, and a static bend radius of 5 × D supports tight routing inside stationary cabinets.