What it is and what it does
The Siemens 4EP3805-6MS00 is a 3-phase filter reactor rated at 5 kVAR at 400 V, 50 Hz. It's built to EN 61558-2-20, the standard for reactors and filter reactors, so it's a known quantity for panel builders and MRO planners dealing with harmonic mitigation or line conditioning. The 14% p (percent impedance) tells you the voltage drop at rated current — this is the figure that governs how much it chokes harmonics. At 134 Hz resonant frequency, it's tuned for the 5th harmonic family (250 Hz on a 50 Hz fundamental), which is where most 6-pulse drive harmonics sit.
Integration notes
IP00 means no enclosure — it's a bare reactor for mounting inside a panel or cabinet. Terminals are free conductor ends, so you'll need your own lugs or ferrules for the connection. The 40 /B thermal class (40 °C ambient, B rise) is standard for this duty; derate if your cabinet runs hotter. Ripple voltage percentages (106 /0 /6 /5) describe the harmonic spectrum it's designed to handle — the 106% figure is the fundamental, and the 6% and 5% are the dominant harmonic orders. That's the spec sheet detail that tells a commissioning engineer whether this reactor will saturate on a given drive's PWM output.