What is 1-Gauge 4-Wire Strain measurement method
For strain gauge measurement, various bridge configurations are employed according to the number of strain gauges to be used and measuring purpose. In quarter bridge configuration, three wire method is widely used to remove the effect of temperature to gauge leadwire resistance. However, some measuring error occurs owing to gauge factor correction due to leadwire resistance and variation in the contact resistance of connection part. Our developed 1-gauge 4-wire strain measurement method serves not to induce any measurement error ascribable to the gauge factor correction and contact resistance.
(Japanese Patent No.3546203)
FEATURES (Superiority to 3-wire quarter bridge method)
- Leadwire Resistance
- In conventional method, as bold and shot leadwires as possible are recommended to keep the resistance of leadwires lower. On the contrary, as the 1-gauge 4-wire method is not influenced at all by the leadwire resistance, it is possible to connect a thin and long leadwires to strain gauges.
- Contact resistance
- In conventional method, leadwire extension and connection to a measuring instrument are done by soldering or the use of exclusive connector. As the 1-gauge 4-wire method is not affected at all by contract resistance, a modular plug can be used. Because the modular plug makes leadwire extension and connection to the instrument possible by merely plugging in, the efficiency of wiring work and prevention of wiring mistake are achieved and also RoHS-compliant lead free soldering is unnecessary.
1-Gauge 4-Wire Measurement System
With TML data logger model TDS-530, 1-gauge 4-wire method is completed by merely connecting the modular jack to its built-in switching box and with TDS-602/TDS-303 data loggers to the exclusive external switching boxes. (Wiring-saved rosette gauges needs external switching box model SSW-13R regardless of the data loggers.) If TML high speed digital dynamic strainmeter model DRC-3410 is used, dynamic 1-gauge 4-wire strain measurement becomes possible.