Problems with capaturing signal

[blackbear]

Dear all,

I bought a model and my amplifer is injecting a pure sinewave of current source of 2A. I measure the current though a resistor shunt and at my labview model i use a divider to divide by the resistor value to get back my current in graphs.However i realise i need to press run button of labview at the same time with my start button of amplifer if not labview will not capture.can some 1 pls advise me on how to fully capture my waveform?My waveform is only 0.1seconds. I have attached my model.Pls advse me of any thing to be ammended in my circuit.

cheers
Shawn

[Matti_Autioniemi]

Hi,

Here's a quick and simple approach attached to get you further with your program. You can add your calculations and such on your own. I replaced waveform graph with a waveform chart, so now you can start your program first and your amplifier afterwards. You can adjust the size of the chart history by right-clicking on the chart and selecting Chart history length.

Hope this helps!

- Matti

[blackbear]

Dear Matti,

thankyou for ur advise.i cant see the chart history.when i open up the chart history lenght it just show the buffer size.how do i see the point when my signal is being trigger?

[Matti_Autioniemi]

Buffer size = history length = data points on the graph . Add X Scrollbar by right-clicking on the chart (Visible items->X Scrollbar) or use Autoscale X. Of course you should adjust the buffer size so that the event you want to see fits into buffer.

- Matti

[blackbear]

Dear Matti,

i followed ur steps unfortunately whenever i play ard with the numbers at the chart history by defualt is 4096, and after i key in numbers the waveform is gone. In additon my signal is of a transient waveform is only 0.1 seconds.Will ur chart about to read?How do i set at from 0 to 0.1 seconds?Need ur urgent advise.thankyou sir.

Cheers
Shawn

[Matti_Autioniemi]

Hi,

You have to adjust the buffer before you run your VI. Hmm, maybe the attached example suites better to your needs. The VI acquires data until trigger condition is reached or Stop is pressed. You should adjust the trigger conditions to fit your needs. Do the math after the trigger has been found.

Hope this will get you further!

- Matti