What is the scan rate of read write operation

Mar 5 at 10:45 AM
Edited Mar 5 at 10:47 AM
I just wanted to know that what is the scan rate for every multi writes with one read and also what is the guarantee that data has been written inside the plc. And also is there a way through which i can set the scan rate for my s7-300 plc. I am using siemens s7-300 PLC connected using an Ethernet connection.