RKL4721 by Bosch Rexroth Indramat

The RKL4721 cable belongs to the RKL Motor Power Cables series manufactured by Bosch Rexroth Indramat. It is intended to supply three-phase servo and spindle motors in automated machinery, especially where the wiring must move continuously inside drag-chain guides. The cable combines power and auxiliary control cores in one PUR-jacketed assembly, which keeps routing more compact between the drive cabinet and the motor. It is suitable for machine axes that require both motor power delivery and a compact moving cable package over repeated travel. That can help keep the cable carrier less crowded on machines with limited space around moving axes.

The outer diameter is 17.0 mm, which helps with conduit selection and clamp sizing. Four power conductors rated at 4x4.0 mm² carry the main phase current, and the insulation system is approved for 600 V AC motor circuits. Dynamic motion is accommodated by a minimum bend radius of 7.5xD, and with that radius the cable can withstand up to 5,000,000 bending cycles in an energy chain. Two 1.0 mm² and two 1.5 mm² control cores run parallel to the power conductors for brake or temperature signals, which can reduce the need for an additional auxiliary cable. Keeping these control conductors inside the same jacket helps the entire cable move as one unit and simplifies carrier layout.

The sheath is colored Orange (RAL 2003), making the motor power cable easy to identify during installation. Fixed routing may use a smaller bend radius of 5xD, which helps in tighter cabinet spaces while maintaining conductor geometry. The pair-twisted construction limits mutual capacitance to 0.8 nF/m, and loop resistance is held to 4.95 ?/km to reduce electrical losses over longer runs. The PUR outer jacket resists abrasion and cutting oils, and the cable is suitable for drag-chain use without requiring additional protective tubing. This combination is useful in production equipment where flexible routing, surface durability, and clear visual identification of the motor lead are all important.