Can I Select a Particular Strain to be Used for Shunt Calibration with NI-DAQmx?
Hardware: CompactDAQ>>Analog Input Modules>>NI 9237, CompactRIO>>Analog Input Modules>>NI 9237
When doing shunt calibration in Measurement & Automation Explorer, can I select a specific strain to simulate the load cell with?
No, you cannot select a particular strain to be used. Shunt Calibration puts a large resistor in parallel with one of the bridge resistors to simulate strain. The resistance value of the bridge, combined with this large resistance will create a set amount of strain. This strain will vary from bridge to bridge but the resistance applied is always the same. So on one bridge you may see a strain of x but on the next bridge you may see a strain of y.
Since the ADC's on your strain measurement device are calibrated with NI-DAQmx, the strain calibration in MAX is used for characterizing the bridge, which can be thought as having a linear (mx+b) response. Applying a known resistor will adjust the gain (m) of and applying a specific strain for calibration purposes is not necessary. Null Offset calibration adjusts b.
KnowledgeBase 4TMG659G: Connecting Strain Gauges and Shunt Resistors to the NI 9237
Report Date: 03/05/2010
Last Updated: 10/10/2017
Document ID: 574FAQXK