Three-no-cable live-line identification instrument

Abstract

The invention discloses a three-no-cable live identification instrument, which comprises a transmitter, a transmitting clamp, a receiving clamp and a receiver, the transmitter is internally provided with a pulse transmitting circuit, and the pulse transmitting circuit is used for transmitting a specified direct current signal on a cable shielding layer; the transmitter can be connected with transmitting calipers; the transmitting calipers are used for being clamped at one end of a tested cable; a detection circuit and a judgment module are arranged in the receiver, and the detection circuit is used for detecting the direction and the magnitude of current; the receiving calipers can be connected with a receiver; and the receiver identifies the corresponding pulse current through the detection circuit and confirms whether the cables are the same cable through the judgment module. According to the invention, a tiny direct current signal is applied to the shielding layer of the cable, and the signal is detected at the other end or a proper position of the cable, so that the accurate positioning of the live cable is realized.

Description

Technical Field

[0001] The invention relates to the technical field of cable live identification, in particular to a three-no cable live identification instrument. Background Art

[0002] At present, the location and identification of cables has always been a problem that troubles workers during the maintenance and transformation of power grids. Traditional cable search methods are complicated and time-consuming, and cannot meet the urgency of the project. For cables that are inconvenient to add signals to the shielding layer, or where the other end of the cable is difficult to determine, traditional identification methods are even more helpless.

[0003] The existing cable live identification device has the following problems: 1. High equipment cost: As a professional equipment, the existing cable identification instrument has high R&D and production costs, so the market price is relatively high. For users or projects with limited budgets, purchasing a cable identification instrument may increase a certain financial burden.

[0004] 2. Large size of equipment: Some cable identification instruments are relatively large, which puts certain requirements on the selection of their working site. In a small or confined space, the cable identification instrument may not be used effectively, or additional space may be required to accommodate and operate the equipment.

[0005] 3. Coupling problem of cable identification signal: It is realized through the transmitting caliper. The signal on the transmitting caliper can be coupled to the identified cable, regardless of whether the cable is in operation.

[0006] 4. Anti-50Hz power frequency interference: The running cable may have 50Hz power frequency electromagnetic interference composed of 50Hz unbalanced current, induced 50Hz interference current and cable distributed capacitance current. High-sensitivity receiving calipers need to solve the problem of how to resist 50Hz power frequency interference to ensure accurate identification of the target cable. Summary of the invention

[0007] In order to overcome the above-mentioned shortcomings of the prior art, the present invention proposes a three-no cable live identification instrument, which achieves accurate positioning of the live cable by applying a small DC signal to the cable shielding layer and detecting the signal at the other end of the cable or at an appropriate position.

[0008] The technical solution adopted by the present invention to solve its technical problems is: a three-no cable live identification instrument, including a transmitter, a transmitting clamp, a receiving clamp and a receiver; the transmitter is provided with a pulse transmitting circuit, and the pulse transmitting circuit is used to transmit a specified DC current signal in the cable shielding layer; the transmitter can be connected to the transmitting clamp; the transmitting clamp is used to clamp one end of the cable under test; the receiver is provided with a detection circuit and a judgment module, and the detection circuit is used to detect the direction and magnitude of the current; the receiving clamp can be connected to the receiver; the receiver identifies the corresponding pulse current through the detection circuit and confirms whether the cables are the same cable through the judgment module.

[0009] Furthermore, the pulse transmission circuit of the transmitter is installed in a shell, and a transmission current clamp and a grounding interface are provided outside the shell.

[0010] Furthermore, the transmitter also includes a controller, a visual screen, and operation buttons; the pulse transmission circuit, the visual screen, and the operation buttons are respectively connected to the controller.

[0011] Furthermore, the pulse transmission circuit also includes a power module, and the power module includes a charging module and a charging port connected to the charging module.

[0012] Furthermore, the upper limit of the DC current output by the pulse transmitting circuit is 30mA.

[0013] Furthermore, the detection circuit of the receiver is installed in a shell, and a receiving current clamp, a screen, operation buttons, and a test interface are arranged outside the shell.

[0014] Furthermore, the judgment module uses a CPU to confirm whether they are the same cable based on transmission characteristic analysis and signal processing algorithms.

[0015] The present invention also provides a method for identifying a live cable using a live cable identification instrument without any cables, comprising the following steps: Step 1: Connect the transmitting caliper to the transmitter, connect the receiving caliper to the receiver, and turn on the transmitter and receiver; Step 2: The transmitting clamp is used to clamp one end of the cable under test; Step 3, controlling the transmitter so that the transmitter transmits a pulse current; Step 4: The receiving caliper clamps the cable to be identified; Step 5: The receiver recognizes the corresponding pulse current; Step 6: The receiver determines whether it is the same cable.

[0016] The working principle of the present invention is to accurately locate the live cable by applying a small DC signal to the cable shielding layer and detecting the signal at the other end of the cable or at an appropriate position. This will help improve the detection of live cables. Accuracy, especially in complex power grid environments.

[0017] A high-frequency AC micro signal is applied to the cable shield and detected at the other end of the cable to determine the cable's charged state. This process requires analysis of high-frequency signal transmission and interference suppression.

[0018] It is necessary to have high-precision recognition capability and not be affected by the induced current of the cable shield. By applying an external DC or AC signal, a method is designed to effectively filter the influence of the induced current, thereby avoiding misjudgment during the cable live identification process. This will significantly improve the accuracy of recognition, especially in complex or highly interfering power grid environments.

[0019] The instrument output is set with an upper limit to avoid affecting the operating circuit. The output DC current upper limit is 30mA, and the output voltage is also limited to avoid the output high voltage affecting the operating circuit when the cable layer resistance is large; (mainly achieved by controlling the output power supply through the power monitoring switch, that is, when the load output power is greater than the upper limit, the power detection hardware circuit will output a control signal to shut down the power output).

[0020] The transmitter and receiver provided in the present invention have a friendly human-machine interface, including a display screen and simplified operation of the on-off switch and mode switching, making the daily use of the device more convenient and intuitive.

[0021] Compared with the prior art, the present invention has the following beneficial effects: 1. Unique identification: The cable identification instrument needs to be able to clearly give the identification result, that is, to ensure that the identified cable is unique. This is achieved by detecting the direction and magnitude of the current. Only when the outgoing current flows through only one cable will the cable be identified as the target cable. All other adjacent cables flow through return currents, which have opposite polarities and can be distinguished.

[0022] 2. Safety: The live cable identification instrument needs to work under the premise of ensuring safety. Ensure that the operator will not be exposed to high voltage electricity, and ensure that any grounding wires and other connecting wires will not be damaged during the identification process. Therefore, the equipment needs to have complete safety protection measures, such as protection circuits, isolation transformers, etc.

[0023] 3. Portability and flexibility: Cable identification instruments are usually used in various environments, so they need to have good portability and flexibility. This includes miniaturization, lightweight design, and easy portability and operation. In addition, the equipment needs to have multiple signal output modes and adjustable transmission power to adapt to cables of different types and cross-sectional areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0025] Figure 1 A flowchart of using a cable live identification instrument without any cables to identify live cables according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a transmitter of a cable-free live identification device according to a third embodiment of the present invention; Figure 3 This is a structural schematic diagram of a receiver of a cable-free live identification device according to a third embodiment of the present invention; Figure 4 This is a pulse transmission circuit diagram of a cable-free live identification device according to embodiment 3 of the present invention.

[0026] Reference numerals: 1. Transmitting current clamp; 2. Grounding interface; 3. Visualization screen; 4. Charging port; 5. Operation buttons; 6. Receiving current clamp; 7. Screen; 8. Operation buttons; 9. Test interface. DETAILED DESCRIPTION

[0027] The technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0030] Embodiment 1: like Figure 2 , Figure 3 As shown, the present invention provides a three-no cable live identification instrument, including a transmitter, a transmitting clamp, a receiving clamp and a receiver. A pulse transmitting circuit is provided in the transmitter, and the pulse transmitting circuit is used to transmit a specified DC current signal in the cable shielding layer. The transmitter can be connected to the transmitting clamp. The transmitting clamp is used to clamp on one end of the cable under test. A detection circuit and a judgment module are provided in the receiver, and the detection circuit is used to detect the direction and magnitude of the current. The receiving clamp can be connected to the receiver. The receiver identifies the corresponding pulse current through the detection circuit and confirms whether the cables are the same cable through the judgment module. The pulse transmitting circuit of the transmitter is installed in a shell, and a transmitting current clamp 1 and a grounding interface 2 are provided outside the shell.

[0031] The transmitter also includes a controller, a visual screen 3, and an operation button 5. The pulse transmission circuit, the visual screen 3, and the operation button 5 are respectively connected to the controller. The pulse transmission circuit also includes a power module, which includes a charging module and a charging port 4 connected to the charging module. The upper limit of the DC current output by the pulse transmission circuit is 30mA. Figure 4 As shown in FIG. 1 , a pulse transmission circuit diagram of an embodiment of the present invention is shown.

[0032] The detection circuit of the receiver is installed in a housing, and the housing is provided with a receiving current clamp 6, a screen 7, an operation button 8, and a test interface 9. The judgment module uses a CPU to confirm whether it is the same cable based on the transmission characteristic analysis and signal processing algorithm. The screen 7 and the operation button 8 are connected to the CPU, and the receiving current clamp 6 is connected.

[0033] Embodiment 2: like Figure 1 As shown, the embodiment of the present invention also provides a method for using a three-no cable live identification device, comprising the following steps: Step 1: Connect the transmitting caliper to the transmitter, connect the receiving caliper to the receiver, and turn on the transmitter and receiver; Step 2: The transmitting clamp is used to clamp one end of the cable under test; Step 3, controlling the transmitter so that the transmitter transmits a pulse current; Step 4: The receiving caliper clamps the cable to be identified; Step 5: The receiver recognizes the corresponding pulse current; Step 6: The receiver determines whether it is the same cable.

[0034] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. The three-no cable live identification instrument is characterized by: It includes a transmitter, a transmitting clamp, a receiving clamp and a receiver; the transmitter is provided with a pulse transmitting circuit, and the pulse transmitting circuit is used to transmit a specified DC current signal in the cable shielding layer; the transmitter can be connected to the transmitting clamp; The transmitting clamp is used to clamp one end of the cable under test; the receiver is provided with a detection circuit and a judgment module, the detection circuit is used to detect the direction and magnitude of the current; the receiving clamp can be connected to the receiver; the receiver recognizes the corresponding pulse current through the detection circuit and confirms whether the cables are the same cable through the judgment module.

2. The three-no cable live identification instrument according to claim 1 is characterized in that: The pulse transmission circuit of the transmitter is installed in a shell, and a transmission current clamp and a grounding interface are arranged outside the shell.

3. The three-no cable live identification instrument according to claim 1 is characterized in that: The transmitter also includes a controller, a visual screen, and operation buttons; the pulse transmission circuit, the visual screen, and the operation buttons are respectively connected to the controller.

4. The three-no cable live identification instrument according to claim 1 is characterized in that: The pulse transmitting circuit also includes a power supply module, and the power supply module includes a charging module and a charging port connected to the charging module.

5. The three-no cable live identification instrument according to claim 1 is characterized in that: The upper limit of the DC current output by the pulse transmitting circuit is 30mA.

6. The three-no cable live identification instrument according to claim 1 is characterized in that: The detection circuit of the receiver is installed in a shell, and a receiving current clamp, a screen, operation buttons and a test interface are arranged outside the shell.

7. The three-no cable live identification instrument according to claim 1 is characterized in that: The judgment module uses a CPU to determine whether the cables are the same based on transmission characteristic analysis and signal processing algorithms.

8. A method for identifying live cables using any one of the three-free live cable identification devices according to claims 1-7, characterized in that: The following steps are involved: Step 1: Connect the transmitting caliper to the transmitter, connect the receiving caliper to the receiver, and turn on the transmitter and receiver; Step 2: The transmitting clamp is used to clamp one end of the cable under test; Step 3, controlling the transmitter so that the transmitter transmits a pulse current; Step 4: The receiving caliper clamps the cable to be identified; Step 5: The receiver recognizes the corresponding pulse current; Step 6: The receiver determines whether it is the same cable.

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