Geokon 4410, Инструкция по эксплуатации, Страница: 9 / 22

3
6) Tighten the four 6-32 set screws holding the strandmeter to the two clamps.
Figure 3 - Spacer Bar Position
7)
Remove the spacer bar and place the assembly in the correct location over the strand.
8) Tighten the lower half of the clamps onto the strand using the four cap screws.
9)
Set the zero reading of the gage by completing the following:
a. Loosen the two 6-32 set screws that hold the clamp to the strandmeter shaft.
b. Insert a 10-32 screw (supplied) into the end of the shaft that comes through the clamp.
c. Connect the gage leads to the readout box (see Section 3) and switch to position 'B'.
d. While watching the reading on the readout, gently pull on the 10-32 screw until an
increasing reading is seen.
Do not allow the reading to reach 8000.
e. While holding the reading between 2500-4000 (3000 is recommended), tighten the
two 6-32 set screws using the Allen wrench provided. Tighten them down hard, so
that the gage will not move.
f. Tighten the 6-32 set screws on the other clamp as well.
10)
For strands that are to be embedded in concrete, fill the PVC tube with grease. A 1/4-28
threaded hole (Figure 1) is provided which will accept a standard grease fitting. Screw the
fitting into the hole, fill with grease, and then remove the fitting.
11)
For embedded strandmeters, it is necessary to provide the clamps with a bond breaker. Using
the Aqua-Seal provided, place a layer over the clamp areas on both ends followed by an
overall layer of electrical tape. The purpose of this is to isolate the sensor from stresses other
than those imposed by the tendon.
12)
Initial readings must be taken and carefully recorded along with the temperature at the time
of installation. These readings serve as a reference for subsequent deformation calculations.
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.