What it is and what it does
The Siemens 4EP3600-5DS00 is a commutating choke (line reactor) designed for converter applications, smoothing current ripple and limiting di/dt on the AC line side of drives and rectifiers. It is a 3-phase, 400 V AC rated choke with a maximum continuous current of 35.5 A and a rated current of 31.95 A at 50 Hz. The 0.4 mH inductance and 2% relative inductive voltage drop define its filtering characteristic — sized to protect the converter's input bridge from excessive current rise without dropping too much voltage under load.
Key ratings — what they mean for fit
The 35.5 A maximum (Ithmax) is the thermal limit at 40 °C ambient — the choke can carry this current continuously without exceeding Class B (130 °C) insulation rise. The 31.95 A rated current (ILN) is the design point for the 2% voltage drop; at this current the choke drops about 8 V line-to-line, which the drive's DC bus regulation typically absorbs. The DC rated value of 43.5 A applies when the choke is used in a DC link circuit — a different duty than the AC line side. The IP00 protection class means the choke is open-frame: it must be mounted inside a panel or enclosure that provides the environmental seal. Screw-type terminals accept standard power wiring.
Where it is used
This choke sits between the AC mains and the input of a variable-frequency drive, DC drive, or regenerative converter. It reduces harmonic distortion, limits inrush current, and protects the converter's diodes or IGBTs from commutation notches. In cold-chain or refrigeration applications — where ammonia or CO2 compressors run on VFDs — the choke helps maintain power quality and extends drive life in electrically noisy environments. The open-frame design (IP00) requires panel mounting; the 148 mm width, 139 mm height, and 78 mm depth fit a standard subpanel footprint.