
4
10)
Connect the readout box. To set the transducer to midrange, rotate the turnbuckle until a
reading of approximately 5500 digits is obtained. To use the total range in convergence, set
the meter at 8000. To use the total range in extension, set the meter at 2500.
11)
Tighten the locknuts on the turnbuckle. (See Figure 4 below.)
12)
Initial readings must be taken and carefully recorded along with the temperature at the time
of installation.
Figure 4 - Convergence Meter Installation Detail - Turnbuckle End
2.3 Electrical Noise
Care should be exercised when installing instrument cables to keep them as far away as possible
from sources of electrical interference such as power lines, generators, motors, transformers, arc
welders, etc. Cables should never be buried or run with AC power lines! The instrument cables
will pick up the 50 or 60 Hz (or other frequency) noise from the power cable and this will likely
cause a problem obtaining a stable reading. Contact the factory concerning filtering options
available for use with the Geokon dataloggers and readouts should difficulties arise.
2.4 Removal
To remove the system, loosen the turnbuckle all the way and then remove the convergence
meter. Disconnect the Swagelok fittings on the rods and disassemble the rods to a manageable
length. If the rod string needs to be lengthened (or shortened) for the next installation, cut off the
ferrules and reinstall new ferrules for the next installation.
Summary of Contents for 4425
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