RKL4556 by Bosch Rexroth Indramat

The RKL4556 is a motor power cable manufactured by Bosch Rexroth Indramat for the RKL Motor Power Cables series. It is intended to interconnect servo or spindle motors with their drive controllers, carrying the main supply current while also accommodating feedback or brake circuits in one sheath. The construction supports continuous motion inside cable carriers, so the product is used wherever automated axes need both electrical power and coordinated control within compact mechanical spaces. This combined cable layout helps keep moving cable runs organized in applications that cannot accommodate separate harnesses.

The cable contains 4 power conductors, and each conductor has a cross-section of 2.5 mm², giving it enough copper area to handle typical inverter outputs for medium-frame motors. A mutual capacitance of 0.7 nF/m keeps reactive current low, which minimizes drive-side filter loading on long runs. Conductor resistance is limited to 7.98 ?/km, which helps reduce voltage drop and heat generation so full torque remains available at the motor terminals. The bundle measures 14.8 mm in overall diameter, allowing dense routing through energy chains and cabinet ducts. Two additional unshielded control pairs provide logic-level signals for temperature sensors, holding brakes, or motor-mounted encoders without requiring a separate cable.

For moving-axis layouts, the cable is rated for drag-chain service, and the halogen-free jacket limits toxic combustion gases in confined plant areas. The sheath is colored RAL 2003 for quick identification and is molded from PUR, a matte, adhesion-free compound that resists oil and cutting fluid. In fixed installations, the assembly tolerates bends down to 5 × D; during continuous flexing, the minimum radius is 7.5 × D, protecting the fine-stranded cores from conductor fatigue.