The Siemens 4EU2732-0CG08-0BA0 is a 3-phase filter reactor rated at 25 kVAR, 400 V, 50 Hz. It's designed for harmonic mitigation and line conditioning in power distribution panels — think VFD input sections, UPS systems, or any nonlinear load that pumps harmonics back onto the bus. The 134 Hz resonant frequency tells you it's tuned to suppress the 5th and 7th harmonics (the dominant ones from 6-pulse drives), not the 3rd. IP00 means it's open-frame, intended for enclosed cabinet mounting, not standalone floor placement. Flat-type terminals simplify busbar or cable lug connections — no ring-tongue crimp needed, just a bolted flat interface.
25 kVAR at 400 V 50 Hz: that's the reactive power compensation the reactor can handle continuously. At 14 % impedance (P(%):14), it's a relatively high-impedance choke — typical line reactors sit at 3–5 %, so this one drops more voltage and provides stronger harmonic attenuation. That impedance also limits inrush current and protects downstream capacitors or drive DC links from transient spikes. The 134 Hz resonance is the self-resonant frequency; above it, the reactor behaves capacitively, so you want that well above the dominant harmonic frequencies you're filtering. EN 61558-2-20 certifies it as a safety isolating transformer/choke standard — relevant for insulation coordination and touch-safe construction in the panel.