Table Of Contents

Selecting a Strain Gage

Last Modified: August 23, 2019

Select a strain gage that meets the needs of your system and application.

  1. Hover over the channel row to see the Configure gear . Click the gear for the channel you wish to add a strain gage to.
  2. Select the desired Bridge Configuration.
  3. Specify the Bridge Resistance (if available), the Excitation Source, Excitation Value, Bridge Offset, and Scaling options for your strain gage.
  4. In the Scaling section of the channel configuration dialog, select the desired Gage Type and additional gage characteristics as needed.

Use the following table to determine which strain-gage configuration your application requires.

Table 1. Strain-Gage Sensor Configurations
Bridge Configuration Gage Type Configuration Type
Quarter Bridge Single Element

Configuration Type I

  • Measures axial or bending strain
  • Requires a passive quarter-bridge completion resistor (known as a dummy resistor)
  • Requires half-bridge completion resistors to complete the Wheatstone bridge
  • R4 is an active strain gage measuring the tensile strain (+ε)
Figure 1. Quarter-Bridge Strain Gage Configuration I
Half Bridge Two Poisson Elements

Configuration Type I

  • Measures axial or bending strain
  • Requires half-bridge completion resistors to complete the Wheatstone bridge
  • R4 is an active strain gage measuring the tensile strain (+ε)
  • R3 is an active strain gage compensating for Poisson’s effect (-νε)
Figure 2. Half-Bridge Strain Gage Configuration I
Half Bridge Two Elements Opposite Sign

Configuration Type II

  • Measures bending strain only
  • Requires half-bridge completion resistors to complete the Wheatstone bridge
  • R4 is an active strain gage measuring the tensile strain (+ε)
  • R3 is an active strain gage measuring the compressive strain (-ε)
Figure 3. Half-Bridge Strain Gage Configuration II
Half Bridge Two Element Chevron

Chevron is typically for torque measurements. The two elements are at a 90 degree angle to each other to create a chevron shape (V-shaped).

Full Bridge Four Element Poisson Same Sign

Configuration Type III

  • Measures axial strain
  • R1 and R3 are active strain gages measuring the compressive Poisson effect (–νε)
  • R2 and R4 are active strain gages measuring the tensile strain (+ε)
Figure 4. Full-Bridge Strain Gage Configuration III
Full Bridge Four Element Poisson Opposite Sign
Configuration Type II
  • Sensitive to bending strain only
  • R1 is an active strain gage measuring the compressive Poisson effect (–νε)
  • R2 is an active strain gage measuring the tensile Poisson effect (+νε)
  • R3 is an active strain gage measuring the compressive strain (–ε)
  • R4 is an active strain gage measuring the tensile strain (+ε)
Figure 5. Full-Bridge Strain Gage Configuration II
Full Bridge Four Element Uniaxial

Configuration Type I

  • Highly sensitive to bending strain only
  • R1 and R3 are active strain gages measuring compressive strain (–ε)
  • R2 and R4 are active strain gages measuring tensile strain (+ε)
Figure 6. Full-Bridge Strain Gage Configuration I
Full Bridge Four Element Dual Chevron

Chevron is typically for torque measurements. The two elements are at a 90 degree angle to each other to create a chevron shape (V shaped), twice.


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