The approach will generally depend on whether you want to store all the data every hour, or just a a sample or two at the end of each hour. 10 samples a second over the course of an hour is probably about 144 Kb which is an awful lot to have sitting in RAM. You would really want to to a stream to disk app in this case. There are plenty of examples of how to do this that ship with LabVIEW. If you just want to save a few samples to disk every hour, than your real problem is keeping track of the time. The easiest way would probably be to just save at the proper loop iteration multiple. If your loop goes around 10 times a second, then you can save when the iteration is a multiple of 36000. If you wanted to avoid a role over problem with the iteration number every 59652
hours, you could choose to use the Get Date/Time in Seconds Vi to keep track of the time instead. Basically inside your loop, you will have a case structure such that the data will save at the proper time.