RKL4335 by Bosch Rexroth Indramat

The RKL4335 cable is a flexible motor power cable produced by Bosch Rexroth Indramat within the RKL Motor Power Cables series. It carries three-phase power and low-level control conductors between drive controllers and servo motors used on robot arms, linear stages, and other moving axes. This assembly is intended for applications with repeated motion in drag chains while maintaining stable electrical transmission and pre-terminated connections. The combined power and control layout also supports compact cable routing where moving equipment has limited space for separate harnesses.

The assembly is rated for 5,000,000 reciprocal bending cycles, indicating long service life under repeated travel. Its bulk cable type is INK0650, which uses a high-flex conductor and insulation arrangement suited to continuous motion. The motor-side connection uses a pre-installed RLS1301/C03 connector, while the drive side uses the matching RLS1302/C03 interface. A dedicated control pair with a cross-section of 0.75 mm² carries brake or sensor signals alongside the power cores, which helps reduce the need for separate auxiliary cabling. During constant travel, the cable must not be bent tighter than a dynamic radius of 7.5 × D, because tighter routing can shorten cable life and increase stress on the shield and conductors.

The jacket compound is halogen-free, which helps reduce corrosive gas release during an electrical fault. Main voltage conductors use a larger 1.5 mm² cross-section to support servo current peaks while limiting temperature rise during operation. For stationary installation, the bend radius may be reduced to 5 × D without harming normal cable performance. The cable also tolerates torsional movement up to ±180°/30 cm, making it suitable for rotating axes and swivel applications. This flexibility helps reduce twisting stress along the cable path during repeated motion.