Should time consuming functions be written in a sub-sequence or a LabVIEW VI?

[Tennessee]

I'm new to Teststand and I want to make sure I have the correct idea about the proper use of programming techniques using Teststand.  I got the impression that Teststand is used to sequence through tests using building blocks from LabVIEW, LabWindowsCVI or some other high level language.  With this thinking, I proceeded to write a 5 hour monitoring routine in LabVIEW and called it from a Teststand step.  I've written the routine to exit if the Teststand execution is terminated.  I want to know if this is the correct approach or would it be better to write the 5 hour monitoring routine in a Teststand sub-sequence?  I've been told, by someone with as much Teststand experience as myself (not a lot), that it should be written in a sub-sequence so that it is not executing out of the Teststand engine too long.  Can someone please give me some insight to the proper method?  The test is to monitor the movement of a cable for 5 hours to assure the brakes hold and do not allow more than 1" of movement (not a hard test to code either way).

[RayFarmer]

Hi Tennessee,

If you are going to launch a step which is going to run for 5 hours and not return back into TestStand until it is finish, then why are you going to use TestStand at all?

What is TestStand going to give you that you cannot do in LabVIEW or CVI?

TestStand going to give you a lot of over head, do you actually need this for the task in hand?

The reason you use sub-sequences, is pretty much the same reason you create sub-vi's or procedures in C

The reason you use Teststand, is to make use of the sequencing of a series of tests, logging of results, evaluation of results, generation of reports, user management.

Regards

Ray Farmer

[Odd_Modem]

The nice thing about TestStand is that it logs to a database. If you want some kind of record that shows the execution path of your procedure then a sequence is appropriate. If you only need to plow through the procedure, and it is already done in LabVIEW, then just do it in LabVIEW. Personally, I find TestStand to be a great help in terms of reporting and database logging.

[RayFarmer]

Hi,

But if your step executes for 5 hours without returning to teststand, your not going to get much logging done of any sort.

Regards

Ray Farmer