Applied Geomechanics

• 4-20 mA Tiltmeters and Clinometers
• Portable Tiltmeter System
• 900-Series Biaxial Clinometers (Analog Voltage Output)
• Digital Tiltmeters
• 800-Series Engineering Tiltmeters and Beam Sensors (Analog Voltage Output)
• 700-Series Biaxial Tiltmeters (Analog Voltage Output)
• 500-Series Geodetic Tiltmeters (Biaxial)

• Miniature Tilt Sensors
• Signal Conditioning Units
• Board Level Signal Conditioners

• IRIS Tilt Switch and Controller

• Pro 3600

• Readout Units
• Data Loggers

• Vibrating-Wire Piezometers
• Vibrating-Wire Strain Gages

• Software
• Tape Extensometer
• Calibration
• Installation
• Training

• Complete PDF Product Catalog (12.32 MB)

• Fiber Optic Monitoring Services

• GPS Monitoring Services

• Performance Monitoring
• Real-time Monitoring
• Structural Health Monitoring

All versions of the Model 906 "Little Dipper" In-Place Inclinometer and of the Model 722 Borehole Tiltmeter are submersible to 5 bars (50 meters water depth). Higher pressures can be special ordered. All versions of the "DeepWater" Tiltmeter are submersible to 250 bars (2500 meters depth). Higher pressure units can be special ordered. The Model 510 Geodetic Borehole Tiltmeter has been tested to case failure at 489 bars and is conservatively rated for use to 250 bars (2500 meters depth. Higher pressure units are available.

The main determinants of accuracy for our tiltmeters and clinometers are: repeatability, linearity and temperature coefficient. Accuracy (in engineering units) is obtained by adding the following specifications: repeatability + (linearity x tilt range) + (temperature coefficient x temperature range). Accuracy can be improved by using a lookup table or polynomial to correct for nonlinearity, and by compensating for temperature change (see our article on "Temperature Compensation" elsewhere in the "Applications" section of the website).

In shallow boreholes under 10 meters in depth, the normal installation procedure is to surround the tiltmeter with sand, which holds it stably in place. For deeper holes, we offer a range of custom placement options, including spring centralizers or decentralizers.

Tiltmeters are used to precisely measure the angular rotation at their installtion point. The tilt measurements of several instruments can be used to obtain a displacement profile or map of surface elevation changes.

Accuracy is the degree of conformity of the measured value to the true value for a specified set of operating conditions. For a given instrument, accuracy over a narrow tilt range is always better than over a wide range. Similarly, accuracy is better over a narrow temperature range than over the full operating temperature range of the instrument. Because accuracy depends so strongly on operating conditions, we believe that it is better to compute accuracy for the application at hand than to rely on a worst-case accuracy value for the full operating range of the instrument.