Geokon 6300, Instruction Manual, Page: 9 / 24

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2. INSTALLATION
2.1 Preliminary Tests
Prior to installation, the sensors need to be checked for proper
operation. Each tilt sensor is supplied with a calibration report
that shows the relationship between readout digits and
inclination. The tilt sensor electrical leads (usually the red and
black leads) are connected to a readout box (see Section 3 for
readout instructions) and the current reading compared to the
calibration readings. After backing-off the clamp screw three
full turns, carefully position the sensor against a vertical
surface and observe the reading. It will take a few seconds to
come to equilibrium and the sensor must be held in a steady
position. The readings should be within ±200 digits of the
factory reading, re-tighten the clamp screw three turns.
Note: Vibrating wire tilt sensors are shock sensitive and
severe shocks can cause a permanent offset or even break
the suspension. (The unit will not survive a two foot (0.5 m)
drop onto a hard surface). When transporting the tiltmeter
tighten the locking clamp screw.
Checks of electrical continuity can also be made using an
ohmmeter. Resistance between the gauge leads should be
approximately 180 Ω , ±10 ohms. Remember to add cable
resistance when checking (22 AWG stranded copper leads are
approximately 14.7 Ω /1000' or 48.5 Ω /km, multiply by two for
both directions). The resistance between the green and white
leads varies with temperature. Compare the measured
resistance and ambient temperature to the factors shown in
Table 2 in Appendix B. The resistance between any conductor
and the shield should exceed two megohm.
2.2 Model 6300 Assembly and Installation
1) Connect the safety cable to the bottom wheel assembly.
(See Figure 3.) This is strongly recommended. Not only
can it be used to retrieve the assembly in the event that one
of the joints breaks loose, but it is also very useful in
lowering the assembly into the casing. The alternative is to
hold the tube sections with vice-grips at the top of the
casing.
The bottom anchor is labeled and has no Universal joint,
just the swivel. The safety cable has a loop at its bottom
end which fits over the long bolt used to hold the bottom
anchor to the first tube section. This is shown in Figure 3.
The cable eyebolt is trapped between two nuts.
Figure 3 - Typical Installation
Top Support
Protective Cap
Gage Cable
Inclinometer
Wheel Assembly
Sensor Assembly
Gage Tubing
Bottom Cap
Cable Connector
Casing