Trigger and gate, timing the trigger.

[Companyqwe]

Hi,

I have been trying extract the length of time that the trigger lasts. I am using a photo gate and need to record the amount of time it is blocked.

If anyone can help? 

I can attach my VI if needed.

Thanks. 

[James_W]

As you have not said anything about the OS architechture of the code or anything else, I suggest posting your code will get a faster response from anyone who reads it and can see what you are trying to do.

Do you have any idea of the sensitivity of your sensor device and a ball park for the timing you are trying to measure?

James

[Companyqwe]

I have attached my VI. 

[Companyqwe]

The timing would be around 0.01(sec) to 3.00(sec).

A card could enter the photo gate and exit. I want to find the amount of time the card breaks the beam of the photo gate for. Or the amount of time between the start trigger engaging and the stop trigger engaging.

[Christian_Hartshorne_NIUK]

Hi Companyqwe,

I have been looking into your query and your code. I would just like to firstly verify my understanding of your problem. Are you trying to measure the exact period of time that the Triggered Signals is being generated i.e. The exact amount of time between the Start Trigger and Stop Trigger in the Trigger and Gate2 Express VI? My first impression is that this may be difficult to do using the this Express VI.

Best Regards,

Christian Hartshorne

NIUK

[Christian_Hartshorne_NIUK · Accepted solution]

Hi Companyqwe,

Having looked at your code in a little bit more detail, I suggest that one way in which you may be able to measure the time between your start trigger and your stop trigger is to obtain the time stamp at the point at which your start trigger level is exceeded and then again at the point where the stop trigger level is exceeded. These time stamps values could then be subtracted to determine the total duration of the trigger.

I have constructed a very crude example to illustrate how this could be achieved. You could apply a similar principal to your application.

I hope this helps.

Best Regards,

Christian Hartshorne

NIUK

[Companyqwe]

Hi CJHartshorne,

I have just worked through your example with my code and DAQ device.  I am pleased to say it works. Thanks so much!

Regards Companyqwe.