The Siemens 4EP3801-2US00 is a 3-phase mains choke (line reactor) sized for frequency converter input. It carries a rated current of 40.5 A (maximum 45 A) at 500 V AC, 50 Hz, with an inductance of 0.4 mH and a relative inductive voltage drop of 2% at rated conditions. That 2% drop is the standard impedance match for most VFD input circuits — keeps harmonic distortion in check without dropping too much voltage across the reactor. Mount this on the line side of a variable-frequency drive to smooth out current spikes and limit harmonics. The IP00 rating means it's an open-frame component — lives inside an electrical enclosure, not out in the washdown zone. Terminals are screw-type, so it wires up with standard ring or fork lugs. Total power loss runs 69 W (54 W in the coil plus 15 W in the iron core) at rated load and 40 °C ambient.
Physical footprint: 0.178 m wide, 0.153 m tall, 0.12 m deep. That's about 7 by 6 by 4.7 inches — a compact block for a 40 A three-phase reactor. Thermal class B insulation (130 °C rise) per IEC 60085 means it handles sustained motor drive duty without cooking the windings.