Electronics Lab - Home. Rs232 to sdi-12 circuit. Design Ideas. Welcome to Electronic Circuits/Schematics Directory :: Next.gr. Microplans.com. Strain gauges : ELECTRICAL INSTRUMENTATION SIGNALS. If a strip of conductive metal is stretched, it will become skinnier and longer, both changes resulting in an increase of electrical resistance end-to-end.
Conversely, if a strip of conductive metal is placed under compressive force (without buckling), it will broaden and shorten. If these stresses are kept within the elastic limit of the metal strip (so that the strip does not permanently deform), the strip can be used as a measuring element for physical force, the amount of applied force inferred from measuring its resistance. Such a device is called a strain gauge. Strain gauges are frequently used in mechanical engineering research and development to measure the stresses generated by machinery. A strain gauge's conductors are very thin: if made of round wire, about 1/1000 inch in diameter. Typical strain gauge resistances range from 30 Ω to 3 kΩ (unstressed).
Such demanding precision calls for a bridge measurement circuit.