Siemens 6ES7331-7KB01-0AB0 Analog Input Module — Legacy Replacement. Siemens 6ES7331-7KB01-0AB0 is the exact manufacturer order number for a analog input module in the SIMATIC S7-300 portfolio. Siemens describes this exact reference as: SIMATIC S7-300, ANALOG INPUT SM 331, OPTICALLY ISOLATED, 2 AI, 9/12/14 BITS RESOLUTION, U/I/THERMOCOUPLE/RESISTANCE, INTERRUPT, DIAGNOSTICS, 20 PIN, REMOVE/INSERT W. BACKPLANE BUS. The verified manufacturer lifecycle record is PM500:Discontinued Product or end of PLM & Support.