NI 9207 Current Reading Slow

[ClayT]

Hello,

I seem to have an issue with my NI 9207 card, and I'm not sure of the cause. I am trying to read a RSE 4-20mA current measurement on ai8:15 on my card. After heavily debugging my code and going back to basics, I've found out that it seems to possibly be linked to the DAQ card itself.

All of my testing was performed on a brand new 9133 cDAQ chassis with a fresh Windows install. The only thing I've added since then was NI VISA for an additional part of a test.

I created a basic VI that reads the 9207 ai8:15 in a for loop. DAQmx read was set to N channels, 1 sample for this testing. I am also timing the loop to see how long the read takes. If I set the for loop to only run once, the DAQmx Read takes ~417ms. If I set it to run 20 times, it takes ~8350ms. So the relationship seems linear in that every single read is taking over 400ms to complete! 

My next step was to go into NI MAX. The reading on the card when set to finite samples is also slow. The reading is not 'smooth' like a normal AI reading. There is visual time between samples on the card.

I'm not really sure what to try next. Any help with this is greatly appreciated.

Thanks.

Edit: I've tried this card on a different system. New PC, using a standalone cDAQ 9171. The current measurement completes as normal... so could this be a problem with the new cDAQ 9133?

[ClayT]

I should also mention that after having success with the standalone cDAQ 9171 on my separate PC, I plugged this same cDAQ 9171 into my cDAQ 9133 in question (via USB) and I still saw the slow readings. 

The cDAQ 9133 is (I assume) brand new. I received it from an RMA, so my first assumption is that it  should work properly, but I'm not able to say for certain.

Is there something I'm possibly missing? Maybe my cDAQ 9133 isn't properly configured, and a setting needs to be changed unbeknownst to me? Any thoughts on this?

[ClayT]

Please also see my attached VI that I am now testing on a new PC. Maybe I'm doing something fundamentally wrong here & someone could give me some insight? Below is a reading from NI MAX, which looks good. The other CDAQ is still much slower to update and is far more jerky as well while using NI MAX with the same settings as pictured.

When I run the VI I am attaching on my 9207 card (on both my cDAQ 9133 and my new PC with dual cDAQ 9171s), I still get 417ms read time per read. What am I missing here?

Thanks

[ClayT]

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