Dear CosMecc,

I have already gone through the motor control appnotes. It is not the motor control part I am really concerned about, I am confused on the PC side software part. I know I need to develop a PC side application. If you have gone through any PLC software from the Siemens or Crouzet stable then you may know that the PLC contains some special function blocks. These are complex routines that may be achieved through a myriads of ladder logic of relays, comparators and timers. Since this is a demonstration project so I need to write these SFB. For example I can have a ref speed set with a virtual pot then some closed loop options etc. So I really need some insight on how to handle this and what blocks to include and what not as I do not have any experience in PLCs.