SIMATIC S7-400, DIGITALEINGABESM 421, POTENTIALGETRENNT16 DE; UC 120/230VEINGAENGE NACH IEC1131-2 TYP 2SIMATIC S7-400, DIG.INPUT MOD.SM 421, OPTIC. ISOLATED,16 DI, 120/230V UCINPUTS PER IEC1131-2 TYPE 2