Mains Choke for Frequency Converter Applications
The Siemens 4EU3951-0UC00-0A is a 3-phase mains choke (Netzdrossel f. FU) designed for installation on the line side of a frequency converter drive. Its primary function is to attenuate harmonic distortion, limit inrush current, and provide a degree of protection to the converter's DC-link capacitors against line-side transients. Rated for 1 600 A AC maximum at 480 V AC, 50-60 Hz. Inductance is 0.000008 H with a 2% inductive voltage drop at rated conditions. Coil loss is 540 W and iron core loss is 212 W at 40 °C ambient.
The part carries UL/CSA recognition and is designed to EN 61558-2-20, the standard for safety of transformers, reactors, and similar equipment. This provides a defensible compliance basis for tender submissions and panel certification audits. Thermal class H per IEC 60085 means the insulation system can withstand a continuous operating temperature of 180 °C, which is typical for high-current, high-loss components in industrial environments.
Physical Integration and Mounting
The choke measures 0.385 m high, 0.41 m wide, and 0.229 m deep. Main circuit connections are via flat-type terminals, which are standard for high-current busbar or cable-lug connections. Verify the terminal dimensions against your busbar drilling pattern or cable lug width during panel layout. The 1 440 A operational current rating (I LN) at rated conditions is the continuous current the choke is designed to carry under nominal voltage and frequency.