NI 9269

[maccapple]

Hi,

I want to use NI 9269 for sine wave voltage generation. I can very well do it with one channel. Can I stack the channels for generating higher voltage? The specs says it can reach 40V with stacking of all 4 channels . It works with DC voltage. but not sure if it should work with AC voltage.(the channels may not be in sync?)

Also want to generate more current as a separate project. For generating more current, the manual asks for parallel connection for getting upto 20mA.. Is it true for AC current?

[GerdW]

Hi maccapple,

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@maccapple wrote:

Can I stack the channels for generating higher voltage? The specs says it can reach 40V with stacking of all 4 channels .

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When the manual says you can stack the channels then you can do that!

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@maccapple wrote:

It works with DC voltage. but not sure if it should work with AC voltage.(the channels may not be in sync?)

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What is your definition of "AC voltage"? Each channel can output ±10V and you can stack them…

(Keep in mind the specs for slewrate and settling times when you want to output higher frequency signals.)

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@maccapple wrote:

Also want to generate more current as a separate project. For generating more current, the manual asks for parallel connection for getting upto 20mA.. Is it true for AC current?

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You cannot control the current sourced by this module: do you want to do so?

[maccapple]

Thanks GerdW,

Probably I did not clarify it in the previous post. Let me be specific.

I want to generate up to 40V AC/60Hz. Stacked all 4 channels . This works perfect if I apply DC output from the module. When I switch to AC output from DC output, with everything else remaining the same, the output voltage does not increase. It actually decreases. I suspect the ac output from each channel may be out of sync with respect to each other.

Regarding the second topic of current output, whatever voltage I apply, the max current can be only 10 ma. What I read in the documents is, I can increase the current output to 20mA max by connecting the output voltages of individual channels in parallel. I never tried this but if I want to get output voltage at 60 Hz, even this might not work ,if the channel outputs are out of sync.

I don't have oscilloscope to confirm.

Hope this makes it clear.

[GerdW]

Hi maccapple,

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@maccapple wrote:

I want to generate up to 40V AC/60Hz. Stacked all 4 channels . This works perfect if I apply DC output from the module. When I switch to AC output from DC output, with everything else remaining the same, the output voltage does not increase.

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I don't see any "DC / AC switch" in the manual/datasheet.

So what are you talking about?

[maccapple]

Please see the picture on the left side

[maccapple]

I just got oscilloscope and interestingly what I noticed is, the channels are perfectly in sync but if I connect negative of channel 0 to positive of channel 1, then channel 1 waveform drops to zero.Channel 0 still continues to output desired waveform

[GerdW]

Hi maccapple,

what happens when you don't switch to AC mode, but stay in DC mode?

[maccapple]

DC mode works as expected, adding the voltages to max 40V

[GerdW]

So your problem is solved!?

[maccapple · Accepted solution]

My problem was limited to AC only .but now I am able to get 40V AC as well.😀 Unfortunately I could not make out what was wrong before.😡 

Anyway thanks for your support