Applying a scale progmatically?

[punkmonkey]

I am trying to progmatically set the scale of a DAQmx channel in LV8. This system is used to test 1000s of devices therefor it is not practical to have a named custom scale for each one. Is there some way to progmatically create a custom scale and assign it to a DAQmx channel?

[devchander]

Do you mean a common custom scale for all Channels?

[punkmonkey]

Basically in the setup I have up to 7 distinctive channels that each would need it's own scaling depending on the type of transducer we are measureing. There will always be at least 2 and each channel would have it's own scaling. The scaling I am wanting to apply is the trasnducers sensitivity.

[Laura F.]

Hello,

It is possible to use a different scale for each channel in your analog input task and to set this all up programmatically.  I am attaching an example.  Basically, you have to first create your analog input channels and give them a name.  Then, you use the DAQmx Create Scale VI to create a scale and then DAQmx Channel property node to set the active channel and the scale information.  I have done only two channels, but it can be scaled up.  I have taken a rather brute force approach to creating each scale, but you could use a loop to increment the scale and channel name. 

Let us know if you have further questions.

Thanks,

Laura

[punkmonkey]

Thanx. That looks like what I need to be doing.

[Jason_P]

Hi,

Is there any chance you could resave that example vi in labview 7.1?

Thanks,

Jason

[Laura F.]

Hi Jason,

Absolutely!  Let me know if you can't open the attachment in 7.1. 

Regards,

Laura

[Share_Good]

Hi Laura,

your VI is really helpful.

i have used the same technique to programatically changing the channel custom scale. i thought of taking each channel from the task, change the scaling property of the channel, put it back to the channel list.
i failed to do so because the channel list is read-only. not resettable.

then your VI helped me how to make a channel of the task active and change the settings. Thanks alot..

i feel this should be updated in DAQmx help somewhere because the scaling is different for different sensors and is useful very often.

[NI-Bongo]

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