TIANJIN GREWIN TECHNOLOGY CO.,LTD.
Web:www.grewin-tech.com Wh86-13072088960
Email:[email protected]
TIANJIN GREWIN TECHNOLOGY CO.,LTD.
Address:
2# MeiNian Plaza No.16 DongTing Road,Hexi Distr,300222,Tianjin China
.
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travel a sufficient distance, it is necessary to remove the ground connectionof the cable.
Power cables that have a ring in the ground will weaken the response on the cable path. At
this point, the search range should be increased and return to the point before the response
change. The receiver will be able to determine all the wire loops except the minimum in the cable.
Most cable connectors will show a peak pulse signal at the receiver. The experience of on-site
detection and understanding of the actual situation can determine whether the peak pulse
signalindicates a junction box
.
The cable is usually buried directly under the road outside the metal fence on the road, and
the signal will be coupled to the metal fence. Because the metal fence is close to the antenna at
the bottom of the receiver, tracking becomes difficult. Lift the receiver so that the antenna in the
lower middle of the body is in the same level with the metal fence. This problem can be solved.
The fact that the transmitter signal is connected to the metal pillar of the street light is
almost as effective as the metal shield of the lighting cable itself, because the metal shield of the
lighting cable can generally be connected to the
metal pillar.
For cables coming from wooden poles, concrete poles or lighting columns, the transmitter
can be placed in an inductive mode and the signal is applied by lining the pole at right angles to the
ground.
6. Some Problems in the Detection of Cast Iron Pipes
This underground pipeline detector can be used to search for steel pipes and cast iron pipes
with isolated interfaces.
Some cast iron gas pipelines and tap water pipelines have insulated joints. Transmitter
signals can be applied to the gas meter or water meter. By using jumpers, the insulating gaskets are
bypassed (a connecting magnet can be used on
both sides of the insulating gasket to ensure the
connection of magnets. Make sure the pipes are
well connected and the two connecting
magnets are connected by wires) so as to
guarantee a reliable circuit for the cast iron
pipes entering the house
.
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.
Illustration of Power Cable of Street Lights Detection
