Strain Gauge Resistance Variation Calculation (Example & Formula)

Strain Gauge Resistance Variation Calculation

This article explains how to calculate the resistance change of a strain gauge under specific load conditions. We'll use an example to illustrate the calculation process.

Example:

Calculate the resistance variation for a strain gauge with the following characteristics and load conditions:

• Strain gauge grid length: 1cm
• Number of grid lines: 10
• Gauge factor: 2
• Resistance under no load (R₀): 120Ω
• Strain of the carrier (ε): 50 × 10⁻⁶

Formula:

The change in resistance (ΔR) of a strain gauge is calculated using the following formula:

ΔR = R₀ * GF * ε

Where:

• ΔR: Change in resistance
• R₀: Resistance under no load
• GF: Gauge factor
• ε: Strain

Calculation:

1. Plug in the values:

ΔR = 120Ω * 2 * (50 × 10⁻⁶)

2. Calculate the result:

ΔR = 0.012Ω

Therefore, the resistance variation of the strain gauge under the given conditions is 0.012Ω.

Key Takeaways:

• The resistance change of a strain gauge is directly proportional to the applied strain.
• The gauge factor is a crucial parameter that relates the change in resistance to the applied strain.
• This calculation is essential for accurately interpreting strain measurements from strain gauges.