USB-2404-UI & DASYLab 2022 Basic Setup Issues

[JaredB]

Hello,

I am working on setting up two single axis loadcells from FUTEK (Model #: LCF456) with the USB-2404-UI DAQ in DASYLab. 

I have installed InstaCal, and have successfully added the USB-2404-UI Board, configuring CH 0 and CH 1 as follows: 

• Channel Mode: Bridge
• Bridge Type: Full Bridge
• Range: +/- 62.5 mV/V

However, I do not see an option in InstaCal to input the load cells' calibration data (i.e. Rated Output, Linearity, etc.), are these inputs set somewhere in DASYLab? 

In DASYLab, I have added an Analog Input module (Inputs/Outputs >> MCC-DRV >> Analog Input) and set all the available options as desired. However, I do not see an option within the Analog Input window to set the excitation voltage for the load cells, is this handled through a different module?

After adding a Digital Meter display and running the data collection, I do not see any change in the digital meter value with an applied load on the load cells, any suggestions?

 

 

 

[DAQman]

Futek calibrated your load cell, and you should have received a calibration sheet indicating its exact sensitivity in units of mV/V (millivolt per volt of excitation). You will convert from mV/V to LBS or N using the DASYLab Scale module. If the sensor is not linear, it can use a table of reference points to convert to engineering units.

In bridge mode, the USB-2404-UI will return measurements in mV/V so that the measurement will be small. You need a significant number to scale the measurement to something meaningful like LBS or N. For a 5000 LBS load cell and a sensitivity of 2mV/V, multiply the measurement by 2,500,000 (5000 / 0.002).

Last, I recommend using the 7.8mV/V range in the high-resolution mode.

 

[JaredB]

Thank you for your advice JRys, 

I added a scaling module in DASYLab and set the scaling at 33,266.799 (For a 500lb load cell with a sensitivity of 1.052mv/V). 

When I start the data collection, the digital meter coming off the scaling module reads "###".  However, if I enter a scaling factor of 10,000 I see a value of 78.12499 in the digital meter, which just reflects the positive 7.8mV/V range value I set in InstaCal multiplied by 10,000 and the value still does not change with an applied load.

Any suggestions? 

[DAQman]

When the input reads a max or min range value, it usually indicates something isn't wired right. A button on InstaCal's Configuration panel will show you how it must be connected. It shows you a picture of the connector and where the wires go.