RZS01.1-6-020

The RZS01.1-6-020 is a three-phase passive output filter developed by Bosch Rexroth Indramat for use with PWM-based servo and mains converters in the RZS Sinusoidal Filters series. Installed between the drive and the motor, the filter shapes the pulse-width-modulated voltage into a near-sinusoidal waveform so that cable-borne emissions, motor insulation stress, and acoustic noise are reduced in industrial automation cells.

The filter carries a nominal line current of 20 A, a value that defines the maximum continuous load it can conduct without exceeding its thermal design. It supports output frequencies up to 200 Hz, allowing synchronous motors to run above base speed while still benefiting from reduced dv/dt at the terminals. The drive’s switching pattern must keep a carrier frequency of at least 8 kHz; lower frequencies would create harmonic components that saturate the inductive elements. Cable runs between inverter and machine can reach 400 m because the filter limits reflected wave peaks that normally constrain distance. Power is connected on the input side through terminals U1, V1, W1, clearly separating converter wiring from the motor side.

For the motor leads, the filtered voltage exits the unit on terminals U2, V2, W2, which maintains phase correspondence while providing isolation from the switching edges present upstream. Internal iron-core inductors and damping resistors dissipate up to 120 W of loss during full-current operation; this heat must be removed by natural convection within the cabinet layout. As a member of the RZS Sinusoidal Filters series, the device matches the mechanical footprint and mounting pattern common to adjacent filter ratings, simplifying scalable installations. The production and quality standards of Bosch Rexroth Indramat ensure that the impedance values remain stable over time, so the drive can maintain low common-mode voltage without periodic recalibration.