Siemens logo 6 7 and 8 sps plc expansion modules siemens 6ed1055 1md00 0ba2 the siemens logo 8 am2 rtd expansion module extends the logo 8 programmable logic controllers with 2 x additional analogue inputs each input will accept a 2 or 3 wire pt100 or pt1000 temperature sensor siemens 6ed1055 1md00 0ba2 logo 8 sps plc expansion module am2 rtd