recording data on events

[Shan21]

In my Labview program, I can monitor the current and position. I am trying to store the postion values at specific current events.

How do I use the variables to store these position values at specific current events?

Do I need to use any File I/O function?

[MikeS81]

Hi Shan21,

can you please explain a bit more about what you try to do? Where do you get current and position? Which events do you mean? How long do you want to store these things?

Mike

[Shan21]

I have a servo motor controller which interfaces in Labview. The current in the servo motor is being monitored at various positions .  Feedback about positions is also provided in Labview

When the current rises above a certain threshold limit, the position needs to be recorded.  There will be many occasions when the current will reach the threshold, hence many instances of position need to be recorded.

These "threshold" positions need to be stored so that they could be analyzed further. This means I want to store them even after the program finishes.

[MikeS81]

Hi Shan21,

you can use a queue to send your values to another loop if the current exceed the limit. There you can store it with File I/O functions. Store your values first in a shift register and write it block by block to your file.

Mike

[Shan21]

I would like to record the position data only when the current threshold is reached and not on other instances.

How do I display the contents of the queue to be sure that the data acquired is true? I would like to see the threshold position values on the front panel ideally.

[Shan21]

Can I use a queue to compare previous and current signal values and hence design a trigger? I could then use this trigger to read the position values only on trigger actiavation.

[MikeS81]

Hi Shan,

you can store the old value in a shift register. It´s independet from the queue. Then you can compare the new and the old value.

Mike