Changing From High Resolution to High Speed in FlexLogger™ to Fix Slow Acquisition Rate For Delta-Sigma Modules

Updated Mar 15, 2022

Reported In

Software

  • FlexLogger

Issue Details

  • I want to select between High Speed and High Resolution mode for my delta-sigma C Series device, such as an NI 9213 or 9219, in FlexLogger™. How do I do this?
  • My data is acquired slowly in FlexLogger. The data goes up in steps and is not smooth or fast enough when using my delta-sigma module. How do I fix this?

 

Solution

As of FlexLogger 2019 R1, it is possible to switch between acquisition modes for delta-sigma modules such as the NI 9219 or 9213. This can help to resolve slow acquisition rates and non-smooth data.

To do so, change the Filter parameter in the channel configuration window and choose the mode you want to use.
You will need to go into the Filtering tab to see the Filter Mode control.

Flex 1.png

Flex 2.png

Previous versions of FlexLogger did not split the channel configuration into multiple tabs:

These modules will default to using High-Speed mode if the Filter selection is set to "None".
 

Additional Information

If you are using FlexLogger 2018 R4 or earlier, there is no way to set the acquisition mode for these modules in FlexLogger. The modules will default to using the High-Resolution mode. In this case, you can upgrade to FlexLogger 2019 R4 or perform your acquisition in another software, such as LabVIEW NXG.

The different filtering modes and the time they take to convert 1 piece of data is explained in the datasheet for your module.
For example, the NI 9219 datasheet shows the High resolution mode takes 500 ms to convert a piece of data, limiting the acquisition to 2 Hz.
Meanwhile, the High speed mode takes 10 ms for the conversion, so you can up to 100 Hz.