Testing device for measuring secondary insulation resistance of mutual inductor

Abstract

The utility model relates to the technical field of test equipment, in particular to a test device for measuring secondary insulation resistance of a mutual inductor, which is provided with a switch timing module, an early warning indication module, a wiring detection module, a power supply module and an insulation resistance meter placement module, the switch timing module is composed of a parallel electronic three-way switch and a timing relay. The early warning indication module is composed of an LED lamp and a buzzer. The wiring detection module is composed of a wiring jack, a grounding jack and a test wire. The power supply module is a 12V direct-current power supply; the insulation resistance meter placing module is composed of an insulation resistance meter placing box. According to the utility model, the test is carried out by combining the test device with the field actual situation, the dangerous points existing in the conventional test process are effectively avoided by utilizing the test device, meanwhile, the labor is saved, the working efficiency is increased, and the safety coefficient of the test is improved.

Description

Technical Field

[0001] This utility model relates to the field of testing equipment technology, specifically a testing device for measuring the secondary insulation resistance of a current transformer. Background Technology

[0002] During insulation testing of the secondary windings of a current transformer at the construction site, the winding under test is short-circuited to the megohmmeter, while all other windings are short-circuited to ground. The specific process is as follows:

[0003] 1. Wipe away dirt from the outer insulation surface of the test specimen with a dry, clean, and soft cloth. If necessary, clean it with a suitable detergent. 2. Connect the "E" terminal of the megohmmeter to the grounding terminal of the test specimen, the "L" terminal to the high-voltage terminal, and the "G" terminal to the shielding terminal. Use shielded wire and an insulating shielding rod for connection. Place the megohmmeter horizontally and stably, press the megohmmeter switch and select a suitable voltage. Briefly short-circuit the "L" and "E" terminals with a wire; the pointer should indicate zero. When open-circuited, the megohmmeter pointer should indicate "∞". 3. Connect the "L" high-voltage terminal of the megohmmeter to the winding being measured, and the "E" terminal to the grounding terminal of the test specimen. Then select a suitable voltage range and turn on the megohmmeter output power. 4. After the megohmmeter pointer stabilizes (or after 60 seconds), read the insulation resistance value. 5. After reading the insulation resistance, first disconnect the connection wire to the high-voltage terminal of the test specimen, and then turn off the megohmmeter power. 6. After disconnecting the megohmmeter, short-circuit the test specimen to discharge it and then ground it. In actual operation, this test method has obvious drawbacks:

[0004] (1) The equipment manufacturing processes of different manufacturers in the existing power system are different. The secondary terminal blocks of the instrument transformer are roughly divided into two types: one is to arrange the secondary coil directly on the terminal block in the form of terminal posts, and the other is to install a terminal block on the terminal block to connect the secondary coil in an orderly manner. Because the types of test equipment are different, the test personnel need to adjust the test wiring according to the actual situation on site during the test. During the measurement, the test wiring needs to be manually changed back and forth, which is time-consuming and laborious.

[0005] (2) The instrument transformer equipment is quite tall, and the test leads are prone to swaying during the test. Manual intervention is required to reinforce the test wiring. The insulation resistance of the secondary coil of the instrument transformer is measured at a test voltage of 2500W for 1 minute. The test voltage is high, and the test process is quite dangerous.

[0006] (3) Since the insulation resistance meter has very few wires, when measuring the insulation resistance of the transformer and conducting AC withstand voltage tests on the secondary coil on site, the number of secondary coils is large, so the test personnel often have to process the test wires themselves on site. The process is crude and time-consuming, which seriously affects the test progress. Utility Model Content

[0007] The purpose of this invention is to provide a test device for measuring the secondary insulation resistance of a current transformer, so as to solve the technical problems mentioned in the background art.

[0008] To achieve the above objectives, this utility model provides the following technical solution: a test device for measuring the secondary insulation resistance of a current transformer, comprising a switch timing module, an early warning indication module, a wiring detection module, a power supply module, and an insulation resistance meter placement module; the switch timing module consists of a parallel electronic three-way switch and a timing relay; the early warning indication module consists of an LED light and a buzzer; the wiring detection module consists of a wiring socket, a grounding socket, and test leads; the power supply module is a 12V DC power supply; and the insulation resistance meter placement module consists of an insulation resistance meter placement box.

[0009] Preferably, the parallel electronic three-way switch is used to control the on / off state of the wiring section during the test, and the timing relay is used to set the test time.

[0010] Preferably, the LED light is used to indicate the operating status of the device, and the buzzer is used to sound an alarm when the test device fails.

[0011] Preferably, the wiring socket is used to connect the test wire during the test, the grounding socket is used to connect the grounding wire during the test, and the test wire is used to connect the test equipment during the test.

[0012] Preferably, the test line is made of PA6, PA66, ABS, PBT, or PP material.

[0013] Compared with the prior art, the beneficial effects of this utility model are: this utility model conducts tests by combining the test device with the actual site conditions, effectively avoiding the dangerous points that exist in the conventional test process, while saving manpower, increasing work efficiency, and improving the safety factor of the test. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of a test device for measuring the secondary insulation resistance of a current transformer according to the present invention.

[0015] Figure 2 This is the operational logic diagram of a test device for measuring the secondary insulation resistance of a current transformer according to this utility model.

[0016] In the diagram: 1. Parallel electronic three-channel switch; 2. Timing relay; 3. LED light; 4. Buzzer; 5. Wiring socket; 6. Grounding socket; 7. Test leads; 8. Power supply module; 9. Insulation resistance meter storage box. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] Please see Figure 1 and Figure 2 This utility model provides a technical solution: a test device for measuring the secondary insulation resistance of a current transformer, comprising a switch timing module, an early warning indication module, a wiring detection module, a power supply module, and an insulation resistance meter placement module. The switch timing module consists of a parallel electronic three-way switch 1 and a timing relay 2. The parallel electronic three-way switch 1 controls the on / off connection of the wiring during the test, the timing relay 2 sets the test time, an LED light 3 indicates the device's operating status, and a buzzer 4 alarms when the test fails. The early warning indication module consists of an LED light 3 and a buzzer 4. The wiring detection module consists of a wiring socket 5, a grounding socket 6, and a test lead 7. The wiring socket 5 is used to connect the test lead 7 during the test, the grounding socket 6 is used to ground the wire during the test, and the test lead 7 is used to connect the test equipment during the test. The test lead 7 is made of PA6, PA66, ABS, PBT, or PP material. The power supply module 8 is a 12V DC power supply. The insulation resistance meter placement module consists of an insulation resistance meter placement box 9.

[0019] like Figure 2 As shown, after the test begins, the secondary coil of the Nth group (initially N = 1, LED indicator lit) of the current transformer is energized with 2500V, while the other windings are grounded (LED indicator off); the test lasts for 1 minute. The test is then evaluated to determine if it passes. If it passes, N is incremented by 1, and the test continues. If the test fails, a buzzer sounds, the test setup, equipment, and the condition of the test specimen are checked, and the problem is resolved before restarting the test. The value N is greater than the total number of secondary coils in the test port.

[0020] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A test apparatus for measuring the secondary insulation resistance of a current transformer, characterized in that: It is equipped with a switch timing module, a warning indication module, a wiring detection module, a power supply module, and an insulation resistance meter placement module; the switch timing module consists of a parallel electronic three-way switch (1) and a timing relay (2); the warning indication module consists of an LED light (3) and a buzzer (4); the wiring detection module consists of a wiring socket (5), a grounding socket (6), and a test lead (7); the power supply module (8) is a 12V DC power supply; the insulation resistance meter placement module consists of an insulation resistance meter placement box (9).

2. The test apparatus for measuring the secondary insulation resistance of a current transformer according to claim 1, characterized in that: The parallel electronic three-way switch (1) is used to control the on / off state of the wiring part during the test, and the timing relay (2) is used to set the test time.

3. The test apparatus for measuring the secondary insulation resistance of a current transformer according to claim 1, characterized in that: The LED light (3) is used to indicate the operating status of the device, and the buzzer (4) is used to alarm when the test device fails.

4. The test apparatus for measuring the secondary insulation resistance of a current transformer according to claim 1, characterized in that: The wiring socket (5) is used to connect the test line (7) during the test, the grounding socket (6) is used to ground the grounding line during the test, and the test line (7) is used to connect the test equipment during the test.

5. A test apparatus for measuring the secondary insulation resistance of a current transformer according to claim 1 or 4, characterized in that: The test line (7) is made of PA6, PA66, ABS, PBT or PP materials.

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