IEC is a standard that's supposed to be transportable between plc's
the idea is you can save the logic as a script file, the other language can then convert this into it's own system.
The GX IEC Dev is a good product but due to the existing plc language there is a problem, to make IEC work they have had to create functions (like siemens) however the mitsubishi plcs do not have locally generated memory areas so they use the only areas availlable, the project reserves areas like M bits (1024 & above) & D Memories above 1024 these are configurable but it uses them as temporary memories so uses them over & over again.
You have to maintain the source code as you cannot upload it to iec developer & get it back into iec.
example is in iec it can be a ladder or iec block but when in the plc it will totally different, what may be a complex ladder with lots of branches in iec (or functions) will turn into a set of rungs that contain loads of temps in it
a good example is:
in gxiecDEv:
|X0|----|x1|----[EQ D2 K1]-------(t0)
this in the plc will be
|X0|-----------------------(M1023)
|m1023|----|X1|------------(m1024)
[EQ D2 K1]----|M0123|--|m0124|------(T0)
so although it is good, make sure you maintain the source files & keep them upto date, if someone else changes some code in the plc & doesn't give you the source you can't get it back into GXiec.
