Siemens logo 6 7 and 8 sps plc expansion modules siemens 6ed1055 1ma00 0ba2 the siemens logo 8 am2 expansion module extends the logo 8 programmable logic controllers with 2 x additional analogue inputs each input can be in the range 0 to 10v or 04 to 20ma current loop and has a 10 bit resolution standardized to 0 to 1000 siemens 6ed1055 1ma00 0ba2 logo 8 sps plc expansion module am2