The Siemens 4EP3400-0HS00 is a 3-phase commutating reactor for converter duty, rated 8.1 A continuous with a 9 A maximum, 1.4 mH inductance. It's an open-frame (IP00) component with free cable endings for main circuit connection — designed to sit inside a cabinet, not on the panel surface.
The 8.1 A rated current at 40 °C ambient (thermal class F per IEC 60085) sets the continuous load limit in a converter DC link or AC line application. The 1.4 mH inductance defines the rate of current change (di/dt) it can smooth — critical for limiting commutation notches and reducing harmonic stress on the converter's semiconductors. Total power loss splits into 32.6 W in the coil and 4.5 W in the iron core, summing to 37.1 W; that heat must be managed inside the enclosure. IP00 means no ingress protection — the reactor has no housing, so it requires cabinet-level protection (IP54 or better on the enclosure) and clearance from live parts per IEC 61558-2-20. The free cable endings (no terminal block) mean you'll land the conductors directly with ring or fork terminals; plan for strain relief and a cable entry gland plate.
Panel footprint and mounting
Footprint is 124 mm wide × 122 mm tall × 73 mm deep. This is a chassis-mount component — no DIN rail clip. Allow clearance around the core for airflow; the 37.1 W total loss at full load needs free convection or forced air depending on your cabinet's thermal budget. The free cable endings accept conductors sized for 9 A; strip and terminate per your panel's wiring practice.