MICROMASTER 4 commutation choke 200V-240V 1AC 22.8A substructure FSB-1.4MH not substructure for V20 Electrical choke SINAMICS line choke for SINAMICS V20, as well as the compact frequency converter SINAMICS G110 and the MICROMASTER 4. Line chokes are used to smooth out voltage peaks or to bridge commutation dips. Line chokes also reduce the effects of harmonics on the converter and the network. If the network impedance is <1%, a line choke must be used to reduce the current peaks. The line choke covers the single-phase voltage range 1AC 200 V to 240 V and the three-phase voltage range 3AC 200 V to 600 V. For sizes FSA to FSD it is available as a substructure and for size FSF as a stand-alone version.