Troubleshooting Your Strain Gage Calibration

NI DAQ Assistant

Troubleshooting Your Strain Gage Calibration

Refer to the following list if you receive an error while calibrating your strain gage:

  • Make sure you have an actual strain gage connected to your physical channel, which is at rest (no strain).
  • Check your strain attributes and make sure they reflect the capability of your measurement hardware and your strain gage setup.
  • Make sure you have correctly connected your strain gage. Half-bridge and quarter-bridge setups require completion networks. If your measurement hardware has a built-in completion network, make sure you program it in software or set the completion jumpers in hardware. Additionally, quarter-bridge strain gage setup requires you to connect an external quarter-bridge completion resistor. Always use a precision completion-resistor whose value is equal to the nominal gage resistance of your quarter-bridge strain gage. Refer to your device documentation for details.
  • Make sure you have specified the correct location of your shunt resistor. On some devices, the shunt resistor location is fixed. On other devices, you can choose the shunt resistor location. Refer to your device documentation to see where the shunt resistor is located by default.
  • If you are drawing a lot of current through one or more strain gages, connect the remote sense inputs to your hardware (if supported).
  • If you have long lead wires with large lead resistance, connect the remote sense to compensate for the voltage drop across the leads.
  • Make sure your strain gage is properly bonded to the strain specimen.
  • Make sure your strain gage does not have any short or open circuits.