Geokon 6160, Руководство по установке

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The above remarks apply mainly to structures exposed to sunlight: in these situations it is not
uncommon for the structure to expand and contract differentially during to course of the day. For
land-slide applications where the MEMS sensors are buried in the ground, temperature variations
are very small or non-existent and ground movements are unaffected by temperatures. In these
situations it is not necessary to measure temperatures.
4. DATA REDUCTION
4.1.Tilt Calculation
The output of the MEMS Sensor is proportional to the sine of the angle of inclination from the
vertical. For the ± 15 degree sensor the FS output is approximately ± 4 volts. The reading,
R , in
volts displayed on the RB-500 readout box, and the inclination,

, is given by the equation:

=(R
1
-R
zero
) G degrees
Equation 1 Inclination versus volts .
Where R is the current reading in volts, R
zero
is the reading at

=zero, and G is the Gage Factor
shown on the calibration sheet for the Model 6160 tiltmeter. Note that for measurements of tilt,
i.e changes of inclination, where
R
0
is the initial reading and R
1
is a subsequent reading, the
small zero reading, R
zero
at zero inclination cancels out so that
Calculated Tilt = G(R
1
-R
0
)
Equation 2 Tilt versus volts
4.2. Temperature Correction
The Model 6160 MEMS Tiltmeter has very small temperature sensitivity equal to +1 arc second
per degree centigrade rise. The tilt corrected for temperature is:
Tilt = G(R
1corr
– R
0
) degrees
Where R
1corr
= R
1
– 0.0003 (T
1
-T
0
)
Equation 3 Tilt versus volts corrected for Temperature.
The structure being monitored usually is affected by temperature to some degree. An important
point to note is that sudden changes in temperature will cause both the structure and the Tiltmeter
to undergo transitory physical changes, which will show up in the readings. The gage
temperature should always be recorded, and efforts should be made to obtain readings when the
instrument and structure are at thermal equilibrium. The best time for this tends to be in the late
evening or early morning hours.
For best results the tiltmeter should be shielded from direct
sunlight.