CN203965552U - Hyperchannel low-voltage leakage detector - Google Patents

Abstract

The utility model discloses a multi-channel low-voltage leakage detector, which relates to the technical field of detection devices for current leakage of low-voltage AC lines of 400 volts and below. It includes a housing, and also includes a current transformer for collecting current signals of each phase, a voltage transformer for collecting voltage signals of each phase, and a current transformer and a voltage transformer for collecting current signals and A/D conversion module for analog-to-digital conversion of voltage signals, a microprocessor for processing the data after analog-to-digital conversion and outputting related signals according to the input signal, and a key circuit for inputting operation commands to the microprocessor , a liquid crystal display for displaying the output signal of the microprocessor, a memory for storing data, and a switching power supply module for powering the leakage detector. The detector can realize the search for electric leakage faults while live, without powering off all users in the station area, and does not affect the power consumption of non-faulty users.

Description

Multi-channel low voltage leakage detector

technical field

The utility model relates to the technical field of detection devices for current leakage of low-voltage AC lines of 400 volts and below, in particular to a multi-channel low-voltage leakage detector.

Background technique

In the vast rural 0.4kV low-voltage radio station area, when the performance of overhead lines, power cables, line power equipment, and user electrical equipment insulation components is degraded or damaged, it will directly lead to grounding accidents in the low-voltage power grid, and leakage lines and equipment can easily cause personal injury. An electric shock accident occurs. Under normal circumstances, a single-phase ground fault will not cause severe electrical accidents, and will not cause burning, light, and smoke when the equipment is short-circuited, especially when the buried wire in the user's room or the insulation in the equipment is damaged It is impossible to find the fault from the surface at all. Users or power supply company operators are used to hastily disarming the leakage protector when the investigation is fruitless, burying serious safety hazards.

When a leakage occurs in the 0.4kV low-voltage system, the following methods are currently used to search: 1. Disconnect all low-voltage user equipment in the entire station area, and then try to deliver it door-to-door. 2. Remove all phases A, B, C, and N of the low-voltage outgoing lines of the power distribution cabinet, and conduct a phase-by-phase power test to determine the faulty phase line. In this process, it is necessary to remove and restore the A, B, C, and N outlets many times, and it is easy to cause electric shock accidents. After the faulty phase line is identified, it is still necessary to remove the line branch overlead to determine the specific fault range. The currently used single-phase leakage tester can only check phase by phase, and the power outage time is long during the check process. At home and abroad, there is no professional instrument that can perform three-phase four-wire multi-channel leakage test and search.

Utility model content

The technical problem to be solved by the utility model is to provide a multi-channel low-voltage leakage detector, which can realize the detection of leakage faults with electricity, and does not need to cut off the power of all users in the station area, and does not affect the power consumption of non-faulty users; The lead wire saves a lot of time spent on finding non-faulty lines; it is not necessary to dismantle the low-voltage power distribution cabinet to reverse the outgoing line, reducing working time and avoiding the risk of electric shock.

In order to solve the above technical problems, the technical solution adopted by the utility model is: a multi-channel low-voltage leakage detector, including a housing, characterized in that: it also includes a current transformer located in the housing for collecting current signals of each phase , the voltage transformer used to collect the voltage signals of each phase, the A/D conversion module used for analog-to-digital conversion of the current signal and voltage signal collected by the current transformer and voltage transformer, and the A/D conversion module used to convert the analog-to-digital converted A microprocessor that processes data and outputs relevant signals according to the input signal, a key circuit for inputting operation commands to the microprocessor, a liquid crystal display for displaying the output signal of the microprocessor, a memory for storing data, As well as a switching power supply module for supplying power to the leakage detector, the input terminals of the current transformer and the voltage transformer are provided with terminals for connecting the wires of each phase.

Preferably, the detector further includes a voice output module for converting the signal sent by the microprocessor into a voice signal for output.

Preferably, the microprocessor uses a high-speed STM32F103 type ARM processor or a MCF54418 single-chip microcomputer of Freescale Corporation.

Preferably, the detector also includes a reserved interface circuit electrically connected to the microprocessor.

Preferably, the memory includes RAM memory and FLASH memory.

The beneficial effect produced by adopting the above technical solution is that: the detector measures the current and voltage of each phase line through the current transformer and the voltage transformer, and then analyzes the collected current and voltage data through the microprocessor to obtain Check whether there is any leakage in each phase line. The detector can realize whether there is a leakage fault in each phase line when it is charged. During the search process, it is not necessary to disconnect all users in the station area from power failure, and it does not affect the power consumption of non-faulty users; it is not necessary to remove the branch over-leading wire to accurately determine the branch where the fault point is located. It saves a lot of manpower and time spent on finding non-faulty lines; it does not need to dismantle the low-voltage power distribution cabinet and reverse the outgoing lines, reducing working time and avoiding the risk of electric shock. In addition, the detector has the characteristics of simple structure and low manufacturing cost, and has good prospects for popularization and use.

Description of drawings

Below in conjunction with accompanying drawing and specific embodiment, the utility model is described in further detail.

Fig. 1 is a block diagram of the utility model;

Fig. 2 is the front view structure schematic diagram of the utility model;

Fig. 3 is a top view structural diagram of the utility model.

Detailed ways

As shown in Figure 1, a multi-channel low-voltage leakage detector includes a housing, and also includes a current transformer located in the housing for collecting current signals of each phase, and a voltage transformer for collecting voltage signals of each phase; A/D conversion module for analog-to-digital conversion of current signals and voltage signals collected by current transformers and voltage transformers; microprocessing for processing the data after analog-to-digital conversion and outputting relevant signals according to the input signals device, the microprocessor uses a high-speed STM32F103 type ARM processor or the MCF54418 single-chip microcomputer of Freescale; it is used to input operation commands to the key circuit of the microprocessor; it is used to display the liquid crystal display of the output signal of the microprocessor A memory for storing data, the memory includes a RAM memory and a FLASH memory; a switching power supply module for powering the leakage detector, and a voice output module for converting the signal sent by the microprocessor into a voice signal for output ; The input ends of the current transformer and the voltage transformer are provided with terminals for connecting the wires of each phase; For the convenience of expansion, the detector also includes a reserved interface circuit electrically connected to the microprocessor.

As shown in Figure 2-3, F1, F2, and F3 are function buttons, ON is the power button, and Test is the test button; IA, IB, IC, and IN are current test sockets; UA, UB, UC, and UN are voltage test sockets ; I0 is the zero sequence test socket.

Three-phase four-wire circuit leakage test: Insert the yellow, green, red and black current clamp terminals into the IA, IB, IC and IN current test sockets of the leakage detector respectively, and connect the yellow, green, red and black four voltage The test plugs are correspondingly inserted into the UA, UB, UC, and UN voltage test sockets of the leakage detector; the jaws of the yellow, green, red, and black current clamps are respectively hung on the A, B, C, and N phases of the circuit to be tested; The yellow, green, red, and black voltage alligator clamps are respectively clamped on phase A, phase B, phase C, and phase N of the low-voltage line to be tested. Turn on the power of the tester, press the ON power button, the tester is ready to work, press the F1 leakage test function key button, press the Test test button, the LCD screen will display the current line leakage current value. The current and voltage on each phase line are collected through a current transformer and a voltage transformer respectively.

Leakage test of three-phase three-wire circuit: Correspondingly connect A, B, C three-phase current and voltage lines, do not need to connect N line current and voltage test lines, and the test method is the same as above.

Single-phase circuit leakage test: directly insert the zero-line current transformer test line into the zero-sequence socket I0 of the tester, press the F2 zero-sequence current test button, press the Test test button, and the crystal screen will display the current line leakage current value.

The detector measures the current and voltage of each phase line through a current transformer and a voltage transformer, and then analyzes the collected current and voltage data through a microprocessor to obtain whether there is leakage in each phase line. The detector can realize whether there is a leakage fault in each phase line when it is charged. During the search process, it is not necessary to disconnect all users in the station area from power failure, and it does not affect the power consumption of non-faulty users; it is not necessary to remove the branch over-leading wire to accurately determine the branch where the fault point is located. It saves a lot of manpower and time spent on finding non-faulty lines; it does not need to dismantle the low-voltage power distribution cabinet and reverse the outgoing lines, reducing working time and avoiding the risk of electric shock. In addition, the detector has the characteristics of simple structure and low manufacturing cost, and has good prospects for popularization and use.

In this paper, specific examples are used to illustrate the principle of the utility model and its implementation. The description of the above embodiments is only used to help understand the method of the utility model and its core idea. It should be pointed out that for those of ordinary skill in the art, some improvements and modifications can also be made to the utility model without departing from the principle of the utility model, and these improvements and modifications also fall within the protection scope of the claims of the utility model . the

Claims (3)

1. A multi-channel low-voltage leakage detector, comprising a housing, is characterized in that: it also includes a current transformer for collecting each phase current signal in the housing, and a voltage transformer for collecting each phase voltage signal, using The A/D conversion module is used for analog-to-digital conversion of the current signal and voltage signal collected by the current transformer and voltage transformer, and is used for processing the data after the analog-to-digital conversion and outputting the relevant signal according to the input signal. The device is used to input the operation command to the key circuit of the microprocessor, the liquid crystal display screen used to display the output signal of the microprocessor, the memory used to store data, and the switching power supply module used to supply power to the leakage detector. The input ends of the current transformer and the voltage transformer are provided with connecting terminals for connecting the wires of each phase, and the detector also includes a voice output module for converting the signal sent by the microprocessor into a voice signal for output and communicating with the microprocessor. A reserved interface circuit electrically connected to the processor. 2. The multi-channel low-voltage leakage detector according to claim 1, characterized in that: the microprocessor uses a high-speed STM32F103 type ARM processor or a MCF54418 single-chip microcomputer of Freescale Corporation. 3. The multi-channel low-voltage leakage detector according to claim 1, characterized in that: said memory includes RAM memory and FLASH memory.