The Siemens SIDAC 4EM5004-3CB00 is a single-phase smoothing choke rated for 16 A DC with an inductance of 6.5 mH. It's designed to sit on the DC bus of a drive or power supply, filtering ripple current and protecting upstream components from harmonics. The 690 V rated voltage gives headroom for 400 VAC rectified DC links without derating.
The 16 A maximum DC current (14.4 A rated) is the continuous limit at 40 °C ambient with Class B insulation (130 °C hot-spot). If your DC bus runs hotter than 40 °C, you'll need to derate — the thermal class B curve in IEC 60085 gives the headroom. The 6.5 mH inductance value determines the ripple attenuation at your switching frequency; for a typical 4 kHz IGBT drive, this choke knocks down the current ripple by roughly a factor of 10 compared to no choke. Total power loss splits between the coil (25 W) and the iron core (0.5 W) — 25.5 W dissipated as heat. That's not trivial in a sealed IP00 enclosure; plan for natural convection or forced airflow around the mounting area. The 0.83 W energy content (stored in the magnetic field) is low enough that discharge resistors aren't mandatory, but standard safety practice still calls for a bleed path if the bus capacitance is large.
This choke lands on the DC link of variable-frequency drives, servo amplifiers, or DC power supplies — anywhere you need to smooth rectified DC and limit inrush current. The IP00 rating means it's an open-frame component for inside a panel; no washdown or outdoor exposure. Mounting uses the screw-type or tab terminals (M4 or 6.3 mm fast-on), so it wires into a terminal block or direct to the drive's DC bus bar.