How Do I Increase Interchannel Delay Using NI-DAQmx or Traditional NI-DAQ (Legacy)? - National Instruments

How Do I Increase Interchannel Delay Using NI-DAQmx or Traditional NI-DAQ (Legacy)? - National Instruments: "Using the LabVIEW API
You can manually set your convert (channel) clock using the DAQmx Timing property node. After placing the DAQmx Timing property node, left-click on the property selector and select More»AI Convert»Rate. Then, right-click on the property and select Change to Write to be able to change this property.
 "

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How Do I Eliminate Ghosting From My Measurements? - National Instruments

How Do I Eliminate Ghosting From My Measurements? - National Instruments: "
Select a transducer with lower source impedance.
Reduce sampling rate and increase interchannel delay to allow enough settling time for the amplifier. See KnowledgeBase 292A3QB5: How do I Increase Interchannel Delay Using NI-DAQmx or Traditional NI-DAQ (Legacy)?
Implement a voltage follower or buffer circuit to decrease source impedance to less than 1 kOhm. See KnowledgeBase 208AD10T: Decreasing the Source Impedance of an Analog Input Signal
Arrange signals to minimize voltage swings between channels.
Choose the high-impedance channel as the first channel in the scan list.
Note: This will only help if you are not sampling in round-robin mode.
Avoid multiplexing – sample one channel at a time or switch to a simultaneous sampling DAQ device."

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Coupling between two AI channels - NI Discussion Forums

Coupling between two AI channels - NI Discussion Forums: "2) Channel-to-channel settling crosstalk: signals on one channel influence the measurement on the next channel in the scan sequence. When the multiplexer switches from one signal to the next, the signal at the A/D converter does not switch instantaneously from one to the other. Due to limited bandwidth of the amplifier and the A/D converter, and capacitance in the multiplexers, there is a settling time as the signal transitions from one level to the next. At first blush it usually has the shape of an exponential function, though once that part has settled out there's usually slower effects that aren't exponential. Those slower components of the settling curve are often due to thermal transients and dielectric absorption in capacitors. In any case, if the A/D converter samples the signal before it's through settling adequately to the new level, the new signal will carry some residual influence of the previous channel. Since the curve usually decreases monotonically, waiting longer to settle decreases the amount of influence. So one thing to try is to lower the channel-to-channel sample rate within each scan - if that decreases the noise, then your problem is likely related to settling."

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Coupling between two AI channels - NI Discussion Forums

Coupling between two AI channels - NI Discussion Forums: "On the other hand, the input resistance is very high (> 10 Gohms), and so any charge left on an otherwise unconnected line will determine the voltage on the line. When the multiplexer switches from your connected load cell channel to the unconnected (floating) channel, the charge stored from the first channel remains in the multiplexer circuitry and holds the voltage where it was until a lower impedance is connected and can influence it. This is why the unconnected channel appears to follow the connected one."

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How do I filter out AC noise on a load cell? - NI Discussion Forums

How do I filter out AC noise on a load cell? - NI Discussion Forums:

• A sharp Butterworth filter will work (let's say 12th order with a cutoff freq of 1-2 Hz)
• The easiest way might be to average over a larger number of points to average out the 60 Hz (or 50 Hz) signal.
• A shielded and correclty grounded shield on the cable between the measurement system and the sensor.

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