The Siemens 4EP3600-5US00 is a 3-phase mains choke (line reactor) designed for variable-frequency drives. It filters harmonics and limits inrush current on the line side of the drive, rated for 400/480V AC at 50/60 Hz. The 0.5 mH inductance and 2% relative voltage drop are sized for a continuous operational current of 25.2 A, with a maximum thermal current of 28 A. This is an open-frame (IP00) component — no enclosure, so it mounts inside a panel or cabinet where the ambient temperature stays at or below 40°C. Screw terminals for the main circuit make for straightforward wiring with ring or fork lugs.
What the ratings mean for fit
25.2 A continuous current at rated voltage and frequency. 28 A max thermal current for brief overloads. 2% voltage drop at rated current. Thermal class B per IEC 60085 means the insulation system is rated for a 130°C maximum hot-spot temperature. The 37.4 W copper loss plus 7.7 W iron core loss (45.1 W total) is the heat this choke dumps into the panel — plan ventilation or derating if the cabinet runs above 40°C.
Where it goes in the panel
Mounts on the panel floor or a mounting plate — no DIN rail clip, so allow for screw-down lugs. Dimensions are 0.148 m wide, 0.139 m tall, 0.078 m deep. The IP00 rating means no touch protection; locate it where live terminals are not reachable during operation, or add a finger-safe shield. Wire it between the line supply and the drive input. The 2% voltage drop is consistent with typical drive reactor sizing; no need to adjust the drive's DC bus parameters for this value. Screw terminals accept standard ring lugs for the 25 A circuit.
Lifecycle and sourcing reality
The 5SJ3140-7 and 5SQ2xxx peers in the evidence are miniature circuit breakers, not line reactors — they are not functional substitutes. No direct second-source exists for this specific choke; the 4EP3 series is Siemens' own line of drive input reactors.