What is the best way to zero a 'custom voltage with excitation' sensor from the front panel?

[donavan]

What is the best way to zero a 'custom voltage with excitation' sensor from the front panel?

Thanks for any help

[GerdW]

Hi donovan,

the best way would be to send the 'Zero' command 😉

What kind of answer do you expect?
We don't know anything about your setup! What kind of sensor? How is it connected to the computer/labview? Does it provide a programming interface? (and many more...)

[donavan]

I am using Labview 8.2, a NI 9237 module in a CDAQ, and an Interface Model 1210AF Full-bridge loadcell.  When setting up the sensor in the DAQ Express as a 'custom voltage with excitation' sensor, the Express VI does not allow shunt calibration or the ability to set a zero on the fly.  (It does offer this option for a strain gage sensor). 

Due to our quality system, I have a known calibration value for the sensor (mv/V/EU) and I would rather treat this sensor as a sensor and not a set of gages.

[Jennifer O]

Hi Donavan,

There are two options for zeroing with the NI-9237.  You can perform offset nulling and shunt calibration with a strain task, or if you use custom excitation you can use software compensation.

See the Bridge Balancing, Offset Nulling section in  the Load, Force, and Torque Measurements tutorial. Take a measurement before the strain is applied and subtract this from all subsequent measurements.  See the above tutorial to consider the tradeoff in accuracy between these two options.

Hope this helps,

Jennifer O.
Applications Engineer
National Instruments