Multifunction DAQ

cancel
Showing results for 
Search instead for 
Did you mean: 

No analog input signal in test panel

Hello,

 

I'm a LV beginner and got stuck while trying to measure a DC-voltage.

 

I am using a Dewetron measuring PC (DEWE-2600) on which is (aside of labview) DEWESoft (Version 6.6.3) installed. With this software I could check on the analog input channel from the NI PCI-6251 device I'm using and figured that it's working correctly. It showed the true voltage value (I compared with a multimeter).

 

When I try to measure the same voltage at the same channel with LV (Version 8.6), I don't get any signal in the MAX test panel (except the regular noise-voltage of some mV). I already did the calibration and selftest of the PCI, which worked out fine. But I still got no results.

 

Can someone please tell me what I do wrong?

 

Thanks a lot,

Mpunkt

 

0 Kudos
Message 1 of 4
(3,186 Views)
The MAX test panel is not LabVIEW so I don't know where you are actually doing this read but one obvious source of error is using a different input configuration.
0 Kudos
Message 2 of 4
(3,182 Views)

Well what I did is creating a new VI and inserting the DAQ-assistant. The express task creating opens and I tell the assistant to measure the analog input voltage and I define the physical channel where the source is connected to. (Actually at this point I can't hit the button "next", just the "finish" one. Maybe that's some sign for an error?)

 

If I hit the "finish" button the DAQ-assistant launches. I leave the default settings (I also tried all other ones but it didn't change anything) and let the assistant draw the graph of the voltage input. Already at this point I don't get the correct signal. It just shows a signal at some mV.

Afterwards I changed the DAQ-assistant to a DAQm task and created an "example" program code.

 

I thought that since I don't get an input signal in LV I should try to check the channel with the measurement & automation explorer.

 

Can you please explain or give an example on the topic of different input configurations? Which input configurations should be paid special attention to? Are there any standard errors that might cause my problem?

Is it at least correct to concentrate on the MAX or do you think the error lays somewhere else?

 

Thanx

Mpunkt

0 Kudos
Message 3 of 4
(3,169 Views)
Sorry, I should have been clearer. By input, I meant differential or single ended.
0 Kudos
Message 4 of 4
(3,160 Views)