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If you want to locate the pipeline on or near the road, you can use a single-ended
connection method to connect the transmitter to the valve, and connect the ground cable
to the metal frame of the valve box. Make sure the connecting magnets are in good
contact with the pipes. If necessary, remove paint and rust before connecting.
Sometimes there may be some insulated joints in the pipeline. The transmitter with
higher signal frequency should be applied to the pipeline behind each joint. This will be
tested segment by segment until the entire pipeline is detected.
Combining the above methods can generally successfully track cast iron pipes.
X.Anti Corrosion Coating Inspection
The fault location is to detect the coating damage of the underground
pipeline (pipeline fault refers to the damage of the outer anti-corrosion layer and
the cable fault refers to the damage of the outer sheath). When there is a fault
point, a part of the signal will return through the fault point through the
grounding rod.HZ-5000 model can locate the fault in the underground pipeline
using the A-frame. Specific steps are as follows:
(1) Frequency selection: When using the A-frame to find the damage point of the
underground pipeline anti-corrosion layer, it is recommended to use two frequencies of
128Hzor512Hz.
(2) Target pipeline positioning: Position the target pipeline with the receiver to determine
the general area of the fault. If there is an abnormal signal loss during the pipeline
tracking, it may be that part of the signal leaks from the insulation breakage into the
ground.
(3) Connection of the fault detection line: Insert the fault detection line or A-frame cable
into the receiver input jack.
(4) Receiver mode settings: Adjust the receiver mode key and select the external signal
mode.
(
5) Use the A-frame to position fault points
The electric potential flowing through the A-frame can be detected byHZ-5000 Ereceiver,
and the leaking insulation of the buried pipeline to the ground can be found through the
change of the potential reading (outer sheath of the steel pipe and the outer sheath of the
Summary of Contents for HZ-5000
Page 1: ...HZ 5000 Underground Cable Detector User Manual Huazheng Electric Manufacturing Baoding Co Ltd...
Page 35: ...33 Figure a Illustration of Deeper Pipes Figure b Illustration of T Branch Pipe...
Page 37: ...35 Figure e Illustration of Detection under Steel Mesh Net Illustration of Depth Measurement...
