Dear LabVIEW Team,Overview:I am a relative newcomer to LabVIEW 7 but have many years of experience in Mechanical Test. I am currently working with a pair of PCB Piezotronics 3-component load cells. I would like to use LabVIEW 7 as a data acquisition system with these load cells. To do so I have an SCXI-1001 12 module chassis. I am connecting a load cell to an SCXI-1121 block/module. The device is set at 10VDC excitiation, which is recommended by the manufacturer.Global Channels with key load cell data:To begin, I initialize three Global Channels with the MAX. These channels are for Custom Voltage with Excitation. In each channel I use the “Table” feature to record and set up a tabl;e based on the manufacturer’s calibration info. This cal info is for each of the three strain gages that make up the load cell. I input the data as follows:mV/V Load (Lbs)0 00.001662 10…0.008334 5050 being the maximum load. These are created as three Global Channels (Fx, Fy, and Mz)VI Development:To create a new vi and use the DAQ-Assistant as follows:1. Select “New” on LabVIEW 7 entry screen2. activate DAQ Assistant3. select Analog input4. select Custom Voltage with Excitation5. select the three Global Channels (Fx, Fy, and Mz)6. Hit test button to run and look at dataThe test data is confusing. If I use the “excitation for scaling” it tends to place the reading for each gage at its maximum. As the gages are unloaded I find this surprising.In addition, if I opt to step away from any scale and consider the system a full bridge, the readings will all be 0.005 volt. This is not bad for a strain gage, however, when I load the cells, the voltage readings do not budge. As I am new to the world of SCXI, I was very careful to check jumpers for proper excitation and set up the system. The load cells worked fine this morning on an INSTRON Series 9 software and DAQ system, but not with the LabVIEW.My question is: Has anyone on the LabVIEW team supported this combination of SCXI 1001 chassis with SCXI-1321 block module with a load cell before? Is it appropriate to use load cells with the SCXI-1001 (I don’t see any reason why not). On paper the set-up would seem very straightforward. I simply cannot get any voltage output from these load cells with LabVIEW.Please advise.Thanks,Adzel

LabVIEW

Dear Adzel,

I'm happy to hear that everything is working. Have a great day!

Marni S.
National Instruments

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