Yes, you can specify wait time between iterations.
To do this, go to Injector installation folder (...\NrgGlobal\Injector) and open "vstation.ini" file.
Then find the "waitbetweenruns=5" line;
When you are done with editing, save the "vstation.ini" file.
Note: Make sure to log off all connected rUsers and start rUsers again to see the change during the test execution before starting a new test.