Test short-circuit wire with alarm function

Abstract

A test short-circuit wire with an alarm function comprises a short-circuit unit, the short-circuit unit comprises three first wire clamps and a short-circuit wire, the three first wire clamps are connected through the short-circuit wire, the connecting wire is connected with the short-circuit wire, one end of a primary winding of the voltage transformer is connected with the connecting wire, and the other end of the primary winding of the voltage transformer is connected with the alarm. The secondary winding of the voltage transformer is connected with the NOT gate circuit, and the alarm is connected with the NOT gate circuit. The NOT gate circuit comprises a triode, two ends of a secondary winding of the voltage transformer are respectively connected with a base electrode and an emitting electrode of the triode, two ends of the alarm are respectively connected with a collector electrode and an emitting electrode of the triode, the collector electrode of the triode is connected with the VCC end, and the emitting electrode of the triode is connected with the grounding end. By arranging the connecting line, connection with a test instrument is facilitated, and by arranging the NOT gate circuit on the short circuit unit, the alarm is turned off during a test and automatically turned on to give an alarm after the test is finished.

Description

Technical Field

[0001] The utility model relates to the technical field of high-voltage tests of electrical equipment, in particular to a test short wire with an alarm function. Background Technique

[0002] In high-voltage tests, a voltage value exceeding the rated voltage is usually applied and maintained for a period of time to test the withstand voltage ability and insulation strength of electrical equipment. A test short wire is a wire with good insulation used to short-circuit some parts of the test circuit, so that the short-circuited parts can withstand the test voltage of the same voltage level, that is, there is no voltage drop between the short-circuited parts. When conducting some tests on high-voltage switches, the three phases are short-circuited with short wires and the test voltage is applied. After the test, the three-phase short wire must be disassembled. However, due to human negligence, it may cause the three-phase short wire to be forgotten to be disassembled, resulting in a short-circuit accident, posing a certain threat to both operators and equipment.

[0003] Chinese patent document CN208127461U, publication (announcement) date: November 20, 2018, discloses a short-circuit device. The short-circuit device includes a short wire and an alarm; the number of short wires is multiple, and the multiple short wires are connected end to end in sequence. The head end of the first short wire, the tail end of the last short wire, and the connection points of adjacent two short wires are connection terminals; the connection terminals are provided with connection clips. Its characteristics are: the setting of the alarm can effectively play a prompting role. Turn on the alarm before short-circuiting and turn off the alarm after the test to prompt the tester not to forget to disassemble the short wire, reducing the risk of forgetting to disassemble the short wire after the test; its disadvantages are: first, it cannot be connected to the test instrument; second, when the alarm is turned on, the alarm will keep sounding. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a test short wire with an alarm function. By setting a connection wire, it is convenient to connect to the test instrument. By setting a NOT gate circuit on the short-circuit unit, the alarm is turned off during the test and automatically turned on after the test.

[0005] To achieve the above object, the utility model provides a test short connection wire with an alarm function, which includes a short connection unit. The short connection unit includes three first wire clamps and a short connection wire. The three first wire clamps are connected by the short connection wire. It also includes a connection wire, a voltage transformer, a NOT gate circuit, and an alarm. One end of the connection wire is connected to the short connection wire, and the other end is used to connect to a test instrument. One end of the primary winding of the voltage transformer is connected to the connection wire, and the other end is connected to the ground terminal. The secondary winding of the voltage transformer is connected to the NOT gate circuit, and the alarm is connected to the NOT gate circuit. The NOT gate circuit includes a triode. The two ends of the secondary winding of the voltage transformer are respectively connected to the base and the emitter of the triode. The two ends of the alarm are respectively connected to the collector and the emitter of the triode. The collector of the triode is connected to the VCC terminal, and the emitter of the triode is connected to the ground terminal.

[0006] A second wire clamp is installed at the end of the connection wire connected to the test instrument.

[0007] The test instrument is an insulation resistance tester or an AC withstand voltage tester.

[0008] A switch is provided between the collector of the triode and the VCC terminal.

[0009] A first resistor is connected between the collector of the triode and the VCC terminal.

[0010] A second resistor is connected between the collector of the triode and the alarm.

[0011] The alarm is a buzzer and / or a lamp.

[0012] Compared with the prior art, the utility model has the following technical effects:

[0013] The three first wire clamps of the utility model are respectively used to connect to the A, B, and C phases of the high-voltage switchgear, and the other end of the connection wire is used to connect to the test instrument.

[0014] When the test instrument outputs voltage, that is, the test starts. At this time, the voltage passes through the voltage transformer, and the induced voltage in the secondary winding of the voltage transformer is 1V. That is, the voltage at the base of the triode is 1V at this time. At this time, the triode is cut off and there is no voltage output, and the alarm does not give an alarm.

[0015] When the test is over, the test instrument has no voltage output, the connection wire has no voltage, and the induced voltage in the secondary winding of the voltage transformer is. At this time, the triode conducts, and the alarm works to give an alarm, reminding the staff to remove the short connection wire in time. By setting a NOT gate circuit on the short connection unit, the alarm is turned off during the test and automatically turned on after the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art.

[0017] Figure 1 Structural schematic diagram of the present utility model.

[0018] Figure 2 Circuit diagram of the NOT gate circuit of the present utility model.

[0019] In the figure:

[0020] Short-circuit unit 10, short-circuit wire 11, first wire clamp 12;

[0021] Connecting wire 20;

[0022] Second wire clamp 30;

[0023] Voltage transformer 40;

[0024] NOT gate circuit 50, triode 51, switch 52, first resistor 53, second resistor 54;

[0025] Alarm 60. Specific implementation manner

[0026] The following details the embodiments of the present utility model. The examples of the embodiments are shown in the accompanying drawings. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present utility model, and should not be construed as a limitation to the present utility model.

[0027] Please refer to Figure 1 、 2 , a test short-circuit wire with a built-in alarm function, including a short-circuit unit 10. The short-circuit unit 10 includes three first wire clamps 12 and a short-circuit wire 11. The three first wire clamps 12 are connected by the short-circuit wire 11. It further includes a connecting wire 20, a voltage transformer 40, a NOT gate circuit 50, and an alarm 60. One end of the connecting wire 20 is connected to the short-circuit wire 11, and the other end is used to connect to a test instrument. One end of the primary winding of the voltage transformer 40 is connected to the connecting wire 20, and the other end is connected to the ground terminal. The secondary winding of the voltage transformer 40 is connected to the NOT gate circuit 50, and the alarm 60 is connected to the NOT gate circuit 50. The NOT gate circuit 50 includes a triode 51. The two ends of the secondary winding of the voltage transformer 40 are respectively connected to the base and the emitter of the triode 51. The two ends of the alarm 60 are respectively connected to the collector and the emitter of the triode 51. The collector of the triode 51 is connected to the VCC terminal, and the emitter of the triode 51 is connected to the ground terminal, that is, connected to the GND terminal.

[0028] Three first wire clamps 12 are respectively used to connect with the A, B, and C phases of the high-voltage switchgear. The other end of the connecting wire 20 is used to connect with the test instrument. By setting the connecting wire, it is convenient to connect with the test instrument.

[0029] When the test instrument outputs voltage, the test starts. At this time, the voltage passes through the voltage transformer 40, and the induced voltage in the secondary winding of the voltage transformer 40 is 1V. That is, the voltage at the base of the triode 51 is 1V at this time. At this time, the triode 51 is cut off and there is no voltage output, and the alarm 60 does not give an alarm.

[0030] After the test is completed, the test instrument has no voltage output, the connecting wire 20 has no voltage, and the induced voltage in the secondary winding of the voltage transformer 40 is 0. At this time, the triode 51 conducts, and the alarm 60 works to give an alarm, reminding the staff to remove the short-circuit wire in time. By setting a NOT gate circuit on the short-circuit unit, the alarm is turned off during the test and automatically turns on the alarm after the test is completed.

[0031] In this embodiment, the VCC voltage is 5V.

[0032] Furthermore, a second wire clamp 30 is installed at one end of the connecting wire 20 connected to the test instrument. Installing the second wire clamp 30 facilitates the connection with the test instrument.

[0033] In this embodiment, the test instrument is an insulation resistance tester or an AC withstand voltage tester.

[0034] See Figure 2 , a switch 52 is provided between the collector of the triode 51 and the VCC terminal. By means of the switch 52, it is convenient to disconnect the power supply of the alarm 60 and make the alarm 60 stop alarming.

[0035] Furthermore, a first resistor 53 is connected between the collector of the triode 51 and the VCC terminal, which plays a role in current limiting.

[0036] A second resistor 54 is connected between the collector of the triode 51 and the alarm 60, which plays a role in protecting the alarm 60.

[0037] Specifically, the alarm 60 is a buzzer and / or a lamp.

[0038] The working principle or operation process of the present utility model is as follows:

[0039] During the test process, the alarm 60 does not work. When the test is completed, through the voltage transformer 40 and the NOT gate circuit 50, the alarm 60 emits an alarm signal, reminding the operator to remove the short-circuit wire. At this time, the operator disconnects the switch 52, and the alarm 60 stops alarming, otherwise it will keep alarming.

Claims

1. A test short circuit wire with a built-in alarm function, comprising a short circuit unit (10), the short circuit unit (10) includes three first wire clamps (12) and a short circuit wire (11), and the three first wire clamps (12) are connected by the short circuit wire (11), characterized in that: It further includes a connecting wire (20), a voltage transformer (40), a NOT gate circuit (50) and an alarm (60). One end of the connecting wire (20) is connected to the short circuit wire (11), and the other end is used to connect to a test instrument. One end of the primary winding of the voltage transformer (40) is connected to the connecting wire (20), and the other end is connected to the ground terminal. The secondary winding of the voltage transformer (40) is connected to the NOT gate circuit (50), and the alarm (60) is connected to the NOT gate circuit (50). The NOT gate circuit (50) includes a triode (51). The two ends of the secondary winding of the voltage transformer (40) are respectively connected to the base and the emitter of the triode (51). The two ends of the alarm (60) are respectively connected to the collector and the emitter of the triode (51). The collector of the triode (51) is connected to the VCC terminal, and the emitter of the triode (51) is connected to the ground terminal.

2. The test short circuit wire with a built-in alarm function according to claim 1, characterized in that: A second wire clamp (30) is installed at the end of the connecting wire (20) for connecting to the test instrument.

3. A test short connection wire with a built-in alarm function according to claim 1, characterized in that: The test instrument is an insulation resistance tester or an AC withstand voltage tester.

4. A test jumper wire with a built-in alarm function according to claim 1, characterized in that: A switch (52) is provided between the collector of the triode (51) and the VCC terminal.

5. The test short connection line with a built-in alarm function according to claim 1, characterized in that: A first resistor (53) is connected between the collector of the triode (51) and the VCC terminal.

6. The test short connection wire with a built-in alarm function according to claim 1 or 5, characterized in that: A second resistor (54) is connected between the collector of the triode (51) and the alarm (60).

7. The test short connection line with a built-in alarm function according to claim 1, characterized in that: The alarm (60) is a buzzer and / or a lamp.

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