04-22-2015 03:57 PM
Hi,
I downloaded the Hioki power anayzer 3390 labview driver from the hioki website and i can graph measurments from my power meter in labview over ethernet.
It does a read every 100ms of the values i specifiy in an array in labview.
I'd like to log this data in a TDMS file in labview.
How do i configure the signal names ( channel names) easily in a TDMS file? I will have 40 channels/Signals logged
Most of the labview demos are creating TDMS from some fancy express VIs which makes the process easier.
All i have are some doubles which update every 100ms which need to find their way into TDMS with the relevant channel names. Voltage 1 , Current 2 etc.
I tried the express VIs: "Write to meas file" and "Set dynamic data attributes". The "Set dynamic data attributes" only allows one dynamic data signal name to be modified which seems pointless.
There are currently 4 doubles in my VI, the content of which will change depending on which signals i set for logging.
See attched pic.
James
04-22-2015 09:18 PM
I was able to specify my channel names easily by adding a 1d array of strings to the Write TDMS VI.
Now i just need to add the 4 channels (doubles) to a 1D array and feed them into the write TDMS vi.
Sounds easy but all of the demos i see create arrays using Auto indexing. If I already have 4 doubles , how can i add these simply into a 1D array?
James
04-22-2015 10:01 PM
04-23-2015 11:04 AM
I used the build array function, i then fed the array into the Data input on the TDMS Write.
My TDMS log file now looks like this:
Umn
0
0
0
0
0
0
0
0
It only displays the first channel name (umn) in my array even though i was feeding in 4 channel names. ( its a 1D array of 5 strings )
Any ideas ?
James.
04-23-2015 11:05 AM
correction 1d array of 4 stings
04-23-2015 11:33 AM
I used debug data values in my Build array function :
1
2
3
4
When i logged my tdms file i got
UMN
1
2
3
4
1
2
3
4
1
2
3
4
So its putting all of the data from my 4 channels into one channel.
I want :
umn IRMS P S
1 2 3 4
Every iteration of my loop I add to the TDMS. ( only 1 sample from each channel)
James