Siemens SIMATIC PLC 6AG1231-5ND32-4XB0 SIPLUS S7-1200 SM 1231 4AI WITH   CONFORMAL COATING BASED ON   6ES7231-5ND32-0XB0 ANALOGE   INPUT, SM 1231, 4 AI, +/-10V,   +/-5V,+/-2.5V, +/-1,25 OR   0-20MA/4-20 MA, 15 BIT + SIGN   BIT 6AG12315ND324XB0