Huazheng HZ-5000, Руководство пользователя

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when the target pipeline diameter is large.
If there is any doubt about the depth measurement, the result can be verified by putting
the receiver 0.5 m above the ground and measuring again. If the measured value is
increased by 0.5 m, the depth measurement is correct.
Depth measurement accuracy can reach up to 5% of pipeline depth if conditions permit,
but operators do not know if bathymetric conditions are always appropriate. Please use
the following technique to check for some readings:
Check whether the pipeline is straight. It should be straight at least within 5 meters on
both sides of the measuring point.
Check if the signal within 10 meters is relatively stable. If it is stable, select several more
pointsbesides the original measuring point for depth measurement.
Checking if there are interference lines with coupled signals in the 3 to 4 meters range of
the target line, which is the most common cause of error in depth measurements, and
strong signals in adjacent lines may cause a depth measurement up to 50% deviation of
the buried depth.
Depth measurements are taken at several points slightly off line. The most accurate
depth reading is at the point where the depth is lowest and the position indicated that is
the most accurate position.
(2)80%Depth Measurement
Place the receiver on the ground just above the target line and perpendicular to the
ground. Select the single-peak antenna peak mode, adjust the sensitivity to a suitable
value, and then move the receiver left and right in the vertical direction of the pipe until
the strength bar drops to 80% of the value when it is just above the line. Mark these two
points and measure the distance between them, which is equal to the buried depth of the
target pipeline.