I have a LabVIEW VI that logs multiple columns of data to a TDMS file. When trying to view the TDMS file using DIAdem, I do not see any data showing up in the column titled “Unit.” I know for a fact that there are units that should be written to the file. Why am I seeing this and what can I do to obtain this data?

When using DIAdem, the word “Unit” is a reserved word inside of the program. If you specify in your LabVIEW VI that the name of that column will be “Unit,” then that is why no data is showing up in that column when using DIAdem. This situation can arise when using a LabVIEW VI that is similar to the image below in Figure 1.

Figure 1. Writing to TDMS File with Unit Column.

This image comes from the linked DevZone article below that demonstrates how to write units and descriptions to a TDMS file. In order to be able to have the units column and not experience the problem inside of DIAdem, rename the “Unit” string to “unit_string.”