ข้อมูลทางเทคนิค
ข้อมูลทางเทคนิค
Compensation formulas for strain gage measurements
Compensation Method of Different Gage Factors
If the gage factor of the strain gage (2.00) is different from that of the strain amplifier, the real strain ε can be obtained by the following equation:
SG58

where, ε0: Measured strain
            Ks: Gage factor of strain gage

Compensation Methods of Nonlinearity Error of Quarter-bridge System
An error of nonlinearity in high-elongation strain measurement with quarter-bridge system is found by calculating true strain ε in the following equation:
SG59
Compensation Methods of Effect of Lead Wire Extension
If the lead wire or cable is extended with the quarter-bridge or half-bridge system, additional resistance is initiated in series to the strain gage, thereby decreasing the apparent gage factor. For example, if a 10 m long lead wire with 0.3 mm2 conductors is used, the gage factor decreases by 1%. In the case of the full-bridge system (transducer), the extension decreases the excitation voltage too. In these cases, the real strain ε is obtained by the following equation. (Supposing the gage factor Ks is 2.00):
SG60
Lead wire resistance values
SG61