Carlson Instruments

CARLSON instruments are elastic wire strain meters containing two coils of highly elastic steel wire.

One of the coils increases in length and electrical resistance when a strain occurs, while the other decreases. The ratio of the two resistances is independent of temperature (except for thermal expansion) and therefore the change in resistance ratio is a measure of strain. The total resistance is independent of strain since one coil increases the same amount as the other decreases due to a change in length of the meter. Therefore, the total resistance is a measure of temperature.

Carlson Joint and Foundation Meters

Joint meters and foundation meters are similar to strain meters except they have greater range. This...

Carlson Stress Cell

CARLSON Stress Cells are plates with a strain-meter sensing element mounted on one face.

Carlson Piezometer

A device to measure water pressure in the pores of granular material such as soil.

Carlson Concrete Meter

A rod-like device which simulates a bar of reinforcing steel.

Carlson Resistance Thermometer

Used for the remote reading of temperature where quick response is not required.

Carlson Strain Meter

A device which can be embedded in concrete to reveal the internal deformations.

Carlson MA-6B Readout

Reads all CARLSON instruments.