JPH0334713Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention is suitable for use in searching and identifying electric wires in steel structures such as ships and plants, where both ends are known and the route along the way is unknown. This invention relates to an electric wire search device.

[Conventional technology]

In steel structures such as ships and plants, when you want to confirm the installation position and route of existing electric wires when remodeling or renovating the same structure, conventional methods have been used to easily and clearly search and identify the installation position and route. The device was not present.

[Problem that the invention attempts to solve]

For this reason, conventionally, when it is necessary to search and identify the installation position of electric wires due to the removal of existing electric wires due to remodeling, for example in ships and plants, effective methods have been developed to assist in this search and identification work. Due to the lack of equipment, the work required a lot of effort and time.

[Means for solving problems]

This invention passes a rectangular pulsed DC current in a low frequency band with little shielding effect through the wire to be searched (both ends are known), and detects the static magnetic field induced by this pulsed DC current. The system is configured to search for the wire installation position and identify the wires. That is, since the pulsed DC current uses a steel structure such as a ship or a plant as a current return path, the DC distribution on the return path is diffused. Therefore, the electric wire search is performed by utilizing the fact that a detectable static magnetic field is formed by the undiffused current, that is, the current flowing through the electric wire to be searched. On this occasion,
By using the above-mentioned pulsed direct current,
The influence of disturbance magnetic fields can be removed, making it possible to search for wires with high reliability.

[Effect]

A pulsating static magnetic field according to Ampere's law (generated magnetic field∝current/distance) is generated in a cylindrical shape around the above-mentioned pulsed direct current. Since it is a static magnetic field, it is not magnetically shielded by the electric wire's outer sheath or shield wire elements. Therefore, it becomes possible to detect the amount of change in the pulsed magnetic field externally and search for and identify the electric wire.

〔Example〕

The wire search device according to the present invention includes a pulsed DC power supply section and a magnetic field detector.

The configuration of the pulsed DC power supply section is shown in FIG.
The components of the magnetic field detector are shown in FIG. 2, and an example of how they are connected is shown in FIG. 3.

The pulsed DC power supply unit 10 obtains a rectangular DC pulsed current by switching the DC voltage obtained from the DC power supply 1 at a constant frequency using the pulse gate 2, and one of the outputs is used as the search target. It has a wire connection terminal 3 for connecting to an electric wire, and a ground terminal 4 for connecting the other output to a steel structure.

The magnetic field detector 20 includes a magnetic field detection probe 5 , a magnetic field detection circuit 6 , a magnetic field change amount detection circuit 7 , and a discrimination circuit 8 . The magnetic field detection circuit 6 and the magnetic field detection probe 5 constitute a magnetic field measurement circuit, such as a parametric resonance type, and measure the magnitude of a minute magnetic field parallel to the magnetic field detection probe 5. This measured amount is output to the magnetic field change amount detection circuit 7, and only the magnitude of the magnetic field synchronized with the frequency of the pulsed DC power source is extracted. The determination circuit 8 determines whether the wire search has ended by comparing the output of the magnetic field change detection circuit 7 with a preset amount of change in the magnetic field necessary for determining the wire search.

When searching for an electric wire, one end of the electric wire 30 to be searched is connected to the electric wire connection terminal 3 of the pulsed DC power supply section 10, and the other end is grounded to the steel structure by the grounding electric wire 9, as shown in FIG. .

The explorer uses the magnetic field detection probe 5 of the magnetic field detector 20
Search for electric wires by moving.

By searching for electric wires in steel structures such as ships and plants as described above, it is possible to easily search for existing electric wires.

[Effect of idea]

As described in detail above, the wire search device of the present invention includes a power supply device that flows a rectangular DC pulse current between the wire to be searched and a structure made of a conductive material, and It has a magnetic field detector that detects the induced magnetic field with a probe, detects the amount of change in the static magnetic field due to the pulsed current from this detection signal, and determines whether the electric wire to be searched is detected based on the signal. With this configuration, it is possible to easily search for existing electric wires in steel structures such as ships and plants.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a pulsed DC power supply section according to an embodiment of the present invention, FIG. 2 is a block diagram showing the configuration of a magnetic field detector according to the same embodiment, and FIG.
The figure is a diagram showing a device connection state when searching for electric wires according to the same embodiment. 1...DC power supply, 2...Pulse gate, 3...
Wire connection terminal, 4... Ground terminal, 5... Magnetic field detection probe, 6... Magnetic field detection circuit, 7... Magnetic field change amount detection circuit, 8... Discrimination circuit, 10... Pulse DC power supply section, 20... Magnetic field detector, 30...Electric wire to be searched.

Claims (1)

[Scope of utility model registration request] A DC pulse power supply device that supplies a rectangular DC pulse current obtained by switching a DC voltage at a constant frequency between a wire to be searched and a structure made of a conductive material; A magnetic field detection probe and a magnetic field detection circuit that detect an induced magnetic field, a magnetic field change amount detection circuit that detects the magnitude of the magnetic field synchronized with the signal period of the DC pulsed current from a detection signal of the magnetic field detection circuit, and An electric wire search device comprising: a discrimination circuit that detects and determines the electric wire to be searched based on the output signal of the magnetic field change amount detection circuit.