Geokon 6101, Инструкция по эксплуатации, Страница: 11 / 14

6
Vertical Tiltplates
If the readings are taken on vertically mounted tiltplates, then in order to get the magnitude and direction of the
maximum tilt, it is necessary to have two vertically mounted tiltplates oriented at 90

to each other, e.g., mounted
on adjacent faces of a square column.
θ
1
is the tilt measured on one face
θ
2
is the tilt measured on the other face
Again
And
θ
θ
R

(Tan θ
1
)
2
+(Tan θ
2
)
2 Tan θ
R
=

= cos
–1
( Tan θ
1
/ Tan θ
R
)
θ
1
2
(
Note:
the offset of the tiltmeter is gi en by the
summation
of the two readings on Pegs 1 and 3 and again by the
two readings on Pegs 2 and 4.
Thus… from Pegs 1 and 3 offset is +25 + (–78) = –53/2 = –26.5
from Pegs 2 and 4 offset is –63 + (+11) = –52/2 = –26.0
v
The difference of 1 digit is due to the normal lack of precision inherent in the measurement. This tiltmeter offset
should remain constant.)
6. Troubleshooting ________________________________________________
The main concerns of tiltmeter surveys are the measurement of change in magnitude and direction of rotational
movement. The zero offset of the sensor is not critical because the algebraic difference of the two readings
eliminates the effect. A tiltplate tilted at an angle and located on a stable surface can be read periodically to check
the calibration of the instrument. The sensor itself should not be opened in the field and if the unit fails to work it
should be returned to Geokon for repair.