Siemens 6ES7231-5QD32-0XB0 Analog Input Module. Siemens 6ES7231-5QD32-0XB0 is the exact manufacturer order number for a analog input module in the SIMATIC S7-1200 portfolio. Siemens describes this exact reference as: SIMATIC S7-1200, Analog input, SM 1231 TC, 4 AI thermocouples. The verified manufacturer lifecycle record is PM300: Active Product.