Maximum Sampling Rate for the NI-9211

Updated Apr 24, 2023

Reported In

Hardware

  • NI-9211

Issue Details

What is the maximum sampling rate for the NI-9211, USB-9211 and USB-9211A, and how is it affected by the CJC and autozero channels?

Solution

When performing a thermocouple task, the NI-9211 automatically reads both the cold-junction and autozero channel values and uses them to calculate the temperature every time the scan list is sampled. Both reads count towards the overall sample rate. 

Below is a table that shows maximum allowable sample rates for the NI-9211 in Hz.

Additional Information

Higher sample rates might be obtained by reading the desired thermocouple channel as a voltage channel in an Analog Input task. However, as an Analog Input task, the resulting units are volts, and temperature calculation is not performed by the driver.

The cold-junction compensation sensor can be read using physical channel 4 as a voltage channel. The autozero channel is not available as a physical channel.