I have S7-200 SMART (CPU ST30) with 3 module EM 04AI (4AI TC) . My machine come from china . these modules monitor 12 zone temperature which heat by 12 heater . in my program i have to use pid control for heater digital output . i use step7-Micro/win smart v02.05 software .

in this software i access to only 8 loop PID .

which method can i use for programming to control 12 PID Temp. ?

thanks 

Closed cause question posted twice.

The second thread with the subject s7-200 smart - 4AI TC Programming is published within the conference SIMATIC S7-200.