Hello SOble;

PUT and GET carry a small amount of data (around 160 bytes for a S7-300, as described in the Communication compendium); so the data tranfer should take only a few ms., which will vary depending on the speed of the network connection. Remebmber MPI operates at 187,5 kB, Profibus-DP at 12 MB max, Ethernet, well that depends on the speed of transmission and the loading of the network.

CPU-CPU Communication with SIMATIC Controllers

However, PUT and GET are FBs (FB 14 and FB 15) which must be programmed in the PLC, and which will be called cyclically either by OB 1, or an FC of your choice normally. So in this case your transmission window will be determined by the Main cycle of the PLC, which can take up to 150 ms (the watchdog timer value), but generally lies around  a value of 20-25 ms.

If yu want to reduce this transmission window  cycle you could use a cyclic OB (OB 35 for your CPU) to call FB 14 and FB 15, and set OB 35 cycle time at 10 ms for example (lower cycle times are not garanteed).

Hope this helps,

Daniel Chartier

Hope this helps,

Daniel Chartier