LILY Self-Leveling Borehole Tiltmeter

Using a high-precision electrolytic tilt sensor, units deliver resolutions to 5 nano radians; the dynamic range is ±330 µradians. Units also feature a ±10 deg. leveling range for easy installation downhole. Output is RS-232 or RS-422 (RS-485 full-duplex) and includes timestamp and compass bearing. Data can be saved to file externally or to LILY’s on-board flash memory (75,000 sample max) using fill/stop or cyclic memory modes.

Units are fully submersible to 3000 psi. Titanium is also available for +5000 psi applications. The culmination of over 30 years of tilt sensor experience and expertise, the LILY represents the pinnacle in precision sensor engineering.



Additional Information

Weight 160 oz
Dimensions 42.06 × 2 × 2 in

• Resolution up to 5 nanoradians
• ±330 µradians dynamic range
• ±10° leveling range for easy downhole installation
• RS-232 or RS-422 output options
• Save data externally or to 75,000 sample on-board flash memory
• Fully submersible to 3000 psi (Titanium available for +5000 psi)


• Volcanic and tectonic research
• Hydraulic fracture mapping
• Micro-deformation monitoring
• Deep ocean geophysics

Performance Specifications

ChannelsX tilt, Y tilt, azimuth, temperature
Resolution<5 nanoradians
RepeatabilitySame as resolution under static conditions
Dynamic Range±330 µradians
Self-Leveling Range±10°
Non-linearity0.2% of full span
Frequency Response<1 Hz
Ks Temp Coefficient (%/°C)±0.02%/°C
Kz Temp Coefficient (bias/°C)±3 µradians/°C
Azimuth detectionOn-board magnetic compass, 0° to 360° output
OutputRS-232 and RS-422 standard (user selectable)
Baud rate9600, 19200 (default), 28800, 57600, 115200, 230400
Sample RateUser programmable from 10 samples/sec to 1 sample/day
Output FormatNMEA XDR, Trimble TCM, Ashtech, Simple (Timestamp, X, Y, Temp, Compass, S/N)
On-board Memory2 Megabytes nonvolatile Flash memory (64,000 samples)
Real-time ClockAccurate to 10 minutes/year or better
Power7 to 28 VDC @ 30 mA (< 10 mA sleep); 250 mV ripple max., reverse polarity protected
Environmental-25°C to +85°C operational, -30°C to +100°C storage. 3000 psi
Materials304 stainless steel, nonmagnetic (6Al-4V Titanium available on request: to +5000 psi)


User Manual

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