SIMATIC S7, SM 331 ANALOG INPUT (6ES7331-7RD00-0AB0) SIMATIC S7, ANALOG INPUT SM 331, OPTICALLY ISOLATATED, 4 AI, 0/4 - 20MA, 1 X 20 PIN, F. SIGNALS F. HAZARDOUS AREAS, CAPABLE OF DIAGNOST.,PTB-TESTED SIMATIC S7, SM 331 ANALOG INPUT (6ES7331-7RD00-0AB0)