full bridge strain gauge

A full bridge uses four active strain gauges instead of two, which doubles the output and provides inherent temperature compensation. If all four gauges are bonded to the same material, thermal expansion cancels out. In practice, that means less drift and higher signal-to-noise ratio, especially on long cable runs where voltage drop can be an issue.

Yes, but we typically recommend 1000Ω gauges for concrete. The higher resistance reduces self-heating from the excitation voltage, and the larger grid area averages over the aggregate. For long-term embedment, we supply gauges with waterproofing coatings and heavy-duty leadwires. Surface preparation is key—grind a smooth patch, clean with solvent, and fill any voids with epoxy before bonding.

It depends on the material and power constraints. 350Ω is fine for steel and short-term tests. For concrete, composites, or long-term monitoring with low excitation voltage, 1000Ω is safer because it generates less heat. The higher resistance also helps when you're using long cables, as leadwire resistance has less effect on the measurement.

We provide cyanoacrylate (CN) for quick, room-temperature curing on smooth surfaces. For rough surfaces or higher temperatures, two-part epoxy gives stronger adhesion. For concrete, a smooth layer of epoxy filler under the gauge is recommended. Always degrease the surface and avoid touching the gauge foil. Curing pressure can be applied with silicone rubber pads or clamping.

Yes, that's a common request. If a standard linear or rosette pattern doesn't fit your geometry, we can adjust the grid length, width, or orientation. We've done custom gauges for bolt tensioning, curved surfaces, and high-temperature applications. Lead time is typically 2-3 weeks for a batch of custom gauges.