Creating data file

[jrsalis]

I am writing code to compare a temperature database to a thermocouple reading and based on the comparison, adjust heaters. My inputs are the starting temperature and the degrees per minute that the heat must rise at. Based on this info how, in LabView, do I create this temperature profile to compare the TC reading to.

[Charlie S.]

Hello jrsalis,

I'm sure we should be able to help you get started with this application, but a little more information might help us help you better. Are you reading the starting temperature and degrees per minute from the database or is that what you are attempting to calculate? Also, how do you define your "temperature profile" -- what is the numerical result you are looking to acheive? Any details on an algorithm you have in mind (even if high-level) would be helpful as well.

Thanks! 

[jrsalis]

The starting temperature and the degrees/hour are given by the test engineer. From that I want to create a file that will have all of the temperatures and times. ( Say the starting tem is 200deg and I want 60deg/hr at time 0. The next entry in the file would 210deg at time 10min and so on). The TC data will be compared to the file every minute or so and based if the TC temp is higher or lower than what it should be I will switch relays connected to heating elements. I will be using the following NI Hardware FP1601 Ethernet Interface, FP-AI-110 and two FP 420 relay banks.

Thanks

Jason 

[Charlie S.]

Hi Jason,

I think the easiest thing to do would be to use a shift register with a for loop. Begin with your starting temperature and deg/hr. Let's say you want 6 temperature steps per hour (six increments in your file) and your rate is 60 deg/hr (as in your previous post). That would come out to 200, 210, 220, 230, etc. An example of how you might implement this is attached below (7.1 format -- let me know if you need something earlier). I've implemented it as a text file, though you could make whatever kind of file you like (depending on how you use it in your application).

When you're ready for the comparison part of your application, you can iterate through the text file and compare you current temperature readings to those in the file. Let me know if you have questions about the VI attached below.

Best of luck!