RKL4311 by Bosch Rexroth Indramat

The RKL4311 motor power cable is produced by Bosch Rexroth Indramat within the RKL Motor Power Cables series. It is engineered for moving-axis installations where a flexible, preassembled line must supply power and feedback between Rexroth drive modules and servomotors in automated production cells. The design focuses on durability under constant motion so that energy transfer remains stable in cable tracks and articulated robot joints. It can be routed through cable carriers and robotic axes where repeated motion would quickly fatigue a rigid harness.

The cable diameter is 12.2 mm, giving a moderate outer profile that fits common drag-chain separators. A tough PUR jacket provides abrasion resistance and resists cutting oils while remaining halogen-free to reduce toxic emissions during a fire. The cable has a dynamic bending radius of 7.5xD during motion and a static radius of 5xD once installed, where D is the outer diameter. The design is rated for 5 million bending cycles, which supports repeated movement in high-stroke applications. Identical M40 9-pin connectors are fitted at both ends to create a plug-and-play harness between the motor and drive.

Electrical conductors are dimensioned for servo loads. Each of the three phase cores has a cross-section of 1.5 mm², allowing continuous currents that match 300 V class drives. The cable is rated for 300/500 V, so the assembly can be used in standard industrial cabinets. Two control pairs with a cross-section of 0.75 mm² run alongside the power cores for brake release or thermal sensor wiring. Copper resistance is limited to 13.3 Ohm/km at 20 °C, helping keep voltage drop within normal servo tolerances over typical machine lengths. The symmetrical M40 terminations simplify routing because no orientation change is required during installation.