Improving sampling rate from wheatstone bridge w. 2 channels

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ainsliej
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Improving sampling rate from wheatstone bridge w. 2 channels

Postby ainsliej » Mon Dec 02, 2019 4:09 am

Hi there,
I am collecting Voltage Ratio info from multiple VINT hub ports simultaneously. Some ports get info from a Wheatstone bridge with just one channel attached, others are linked to Wheatstone bridges with two samples. I have noticed a big difference in sampling rate, where the inputs from the Wheatstone bridge with just one channel are at around 50Hz, whereas the ones from Wheatstone bridge with two channels are at 10Hz.

I have setVoltageRatioChangeTrigger(0.0) and setDataInterval(20) to all channels. Can I get a better sampling rate from my Wheatstone bridges with two channels?

Best wishes,
Ainslie

fraser
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Re: Improving sampling rate from wheatstone bridge w. 2 channels

Postby fraser » Mon Dec 02, 2019 10:09 am

Are the inputs/loadcells attached to the DAQ1500 at all times or do you disconnect and reconnect them while its running?

ainsliej
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Re: Improving sampling rate from wheatstone bridge w. 2 channels

Postby ainsliej » Mon Dec 02, 2019 10:14 am

They are connected the whole time

Mattf
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Re: Improving sampling rate from wheatstone bridge w. 2 channels

Postby Mattf » Wed Oct 07, 2020 10:09 am

Hi,
I am having the same issue, There is a data point at 50hz, but it is a repeat, basically a sample at 10hz repeated.
Is there any resolution here?
Working in python. Changing time.sleep does not seem to alter the output from the bridge amplifier... just what is being recorded.

Thanks.
Matt

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mparadis
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Re: Improving sampling rate from wheatstone bridge w. 2 channels

Postby mparadis » Wed Oct 07, 2020 2:13 pm

It turns out the DAQ1500 has one ADC for the two channels, so having both channels open with a short data interval will increase the minimum interval to ~100ms. The specifications for the DAQ1500 have been updated to reflect this.


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