technoac Success CBI-116N, Руководство по эксплуатации

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4.1 Route location methods
1.The Maximum method
This method consists of positioning the electromagnetic sensor in the direction of the magnetic
field created by the utility radiation (fig.4.3). EMD sensor must be positioned horizontally and
the sensor placed in a plane perpendicular to the cable route. In this case the maximum signal
level is observed when the sensor antenna
passes directly above the utility line. The
maximum method is intended for a quick
route location. Flat peaks of the signal
level curve do not allow for high location
accuracy, but enables a quick route
location.
2. The Minimum method
When the EMD sensor in a vertical (transport) position is placed directly above the route the
signal is at its lowest level fig. 4.4. As the distance from the point directly above the pipeline
increases, the signal level first rises sharply then slowly decreases. This is the minimum method,
which is used to determine a more precise
route location (after quick route tracing
using maximum method.
Horizontal
position
Fig. 4.4
Fig. 4.3
Vertical
position