set independent control for rpm and current

[Rajesh_Hariharan]

Hello,

I need some help with labview. I am measuring the current, voltage and rpm of a pump connected to a control box. The control box is also conected to my DAQ. My requirement is I would like to monitor the voltage and current fluctuations on a waveform chart in labview once I run the vi file and monitor the rpm only when I start the pump. WHen I try to run the vi file before the pump is started, I get an error code "200284". I understand that the rpm meter in my vi is not receiving the signals and is terminating the program. How do I set a sparate control for displaying the voltage and current irrespective of whether the pump is started or not? or how do i set a control for the rpm monitor to display only when the pump is started and not affect the voltage and current display part of the VI.

It may sound a bit complicated! please give me your suggestions in how to get this done!

Thanks,

Rajesh

[Zachmx]

Hi Rajesh,

It sounds like you might be getting a timeout error while the DAQ Assistant is waiting for the pump sensor to start. You could try adding a timeout to the input on the DAQ Assistant so the program will wait for the pump to get started without giving you this error.

[Rajesh_Hariharan]

Can you please tell me how to add a timeout to the input on the DAQ Assistant? I am fairly new to Labview and just started learning!

[Zachmx · Accepted solution]

Looking at your code, the DAQ Assistant on the bottom is taking in the RPM data you are looking for. You can right click on the arrow to the left of the "timeout (s)" option near the bottom of the DAQ Assistant ExpressVI and select Create>>Constant. This will create a constant in seconds that represents the time that DAQ Assistant will wait on input. You can base this number on how long you think it will take the RPM input to start.

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It should look something like the above, but you can change the time the ExpressVI will wait to your needs.

[Rajesh_Hariharan]

Thanks a lot Mr.Zach! Your suggstion helped solve my problem!