The Siemens 4EP3904-4DS00 is a 3-phase commutating choke (drossel) designed for converter applications. It carries a rated current of 11 A with a maximum of 12 A, an inductance of 3 mH, and an operating voltage of 600 V AC at 20 Hz. The part is rated for an ambient temperature of 40 °C and is built to thermal class B per IEC 60085. It is recognized under UL/CSA standards, making it suitable for panels destined for North American or European markets.
What the ratings mean for fit
The 11 A rated current and 3 mH inductance are the key selection parameters: this choke limits the rate of current rise (di/dt) in the DC link of a converter, protecting the rectifier diodes and smoothing commutation notches. The 0.75 % relative inductive voltage drop at rated current tells you the choke's impedance at line frequency — low enough to avoid significant voltage sag under load. The 600 V AC operating voltage covers standard 400 V and 480 V three-phase systems with margin. The 20 Hz operating frequency matches the fundamental of many variable-frequency drives running at low output; for 50/60 Hz line applications the choke will still function, but the core losses shift — verify thermal performance if used above 20 Hz. IP00 means the choke is open-frame with no enclosure protection. It must be mounted inside a panel or cabinet that provides the required ingress protection for the environment. The screw-type terminals accept standard ring or fork lugs; strip length and torque follow the manufacturer's recommendation for the terminal size.
Integration and mounting
The choke measures 0.219 m wide by 0.179 m tall by 0.123 m deep (approximately 219 × 179 × 123 mm). It is a panel-mount component — not DIN-rail — so plan for dedicated mounting holes or a chassis plate. The screw terminals for the main circuit are sized for the 11 A continuous duty; use appropriately rated ring lugs. The total power loss is 82.2 W (53.4 W in the coil plus 28.8 W in the iron core), which must be considered in the cabinet thermal budget. Allow adequate airflow around the choke to avoid exceeding the 40 °C ambient rating.
