S7-200CN 3 S7-200CN CPU 17 19 21 RTD 22 EM253 23 SIWAREX MS 24 25 HMI 27 1 29 1-1 !"#$% 29 1-2 #$% 31 1-3 & #$% 33 2 DIP 34 2-1 EM231 EM235 DIP '() 34 2-2 EM231 DIP '() 34 2-3 EM231 DIP '() 35 3 !"#!$%& 36 4 S7-200CN '()* 37