Product Description:

The HMF01.1N-S0K1-M0300-N-480-NNNN is produced by Bosch Rexroth Indramat within the HMF Motor Filters series. Designed for drive systems that use high-frequency pulse-width-modulated outputs, this passive filter module is installed between the converter and the stator connections of a servo or induction machine. By smoothing steep voltage fronts, it protects motor insulation and reduces electromagnetic emission into adjacent cabling, which supports reliable operation of automation cells running multiple axes in close proximity. It shares mechanical dimensions with companion IndraDrive power sections for straightforward panel integration.

Internally, the filter contains three single-phase chokes that create a low-pass network on the drive’s output stage. It is placed on the converter-to-motor output circuit so that all phase currents are processed before reaching the machine windings. The design maintains linear impedance across the 0–100 Hz fundamental range, allowing commanded torque frequencies to pass while blocking higher switching harmonics. To protect insulation, the output voltage is limited to a maximum peak voltage of 1000 V, and the dv/dt at the terminals remains below 1 kV/µs even when the converter uses fast IGBTs.

The assembly is intended for cabinet layouts that keep the iron core upright, and its vertical mounting orientation aids natural convection and simplifies conductor routing. During transient loading, it withstands 150% for 60 s every 10 min, and short surges up to 165% for 2 s can be tolerated, so the magnetic elements do not saturate when the drive delivers overcurrent during acceleration. As a motor filter, the choke combination minimizes bearing currents and acoustic noise without the need for additional RC networks, which is useful on long cable runs and with high switching frequencies.