FBD in flexlogix

[nileshsurya 0]

hi thr u all PLC experts recently i have come across a project in which my client demands tht all the PLC programming be done in FBD the system is a FLEXLOGIX processor with 512k memory , local and local2 racks with some 322 DI/DO and some 25 AI/AO. we have done the programming in ladder and the total memory usage is some where around 224 kb which is some half of the total program memory of 448kb alloted as program memory in the flex CPU. now when we use FBD as programming language then the memory usage is a whopping 390 kb and yet a section of some 50 I/O's is yet to be programmed. now this is a great problem for us as we want the memory to be utilized only 50-60% even if FBD is to be used so i would like to know all the possible tips and suggestions from all ppl in reference to FBD programming as to how tht i can minimize the program size while using FBD. i would also like to know whether RSLOGIX 5K has a facility so that user-defined(or custom)FBD's can be developed. i am in a great problem so i would like to know tips and suggestions as soon as possible waitin for reply from u guys REGARDS NileshSurya