Huazheng HZ-5000, User Manual

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in pipeline detection, which may result in inaccurate position or depth
measurement of the target pipeline or detection of an incorrect pipeline. In many
cases, a certain degree of induction is unavoidable, but by using on-site inspection
experience, some methods can be used to reduce the degree of induction, thus
improving the reliability of detection.
Try to avoid using the inductive connection method to apply the signal,
because the inductive signals may be applied to multiple underground pipelines.
Determine the locations where underground pipelines are complex and
relatively close to each other. Detect from the simple point of the pipeline to the
complex underground pipeline area, instead of starting from the complex
underground pipelines. For example, if there are water pipes, gas pipes, power
cables, etc. in a building, the signals should be applied from valves or other access
points outside the building instead of signals from the building.
Illustration of double-ended connection
Use lower frequency signals if possible to reduce the response to the adjacent pipeline.
If the signal returns to the transmitter through another pipe, double-ended connection
can be used to bypass the ground loop. Because when using the single-ended
connection method, the ground loop signal goes back to the transmitter through other
pipelines. Sometimes the loop signal may be stronger than the target pipeline signal
because the target pipeline is deeper than the signal-carrying pipeline or the loop pipeline
is more conductive than the target pipeline.There will be problems with the detection of
the target pipeline. If there are access points at both ends of the pipeline, using the
double-ended connection method to connect the transmitter is the most effective way to
identify the target pipeline under intensive pipeline conditions. The specific operation is as
follows:
The transmitter is connected to an access point in the target pipeline, and the