CN204241608U - A kind of leakage current testing cassete - Google Patents

Abstract

The utility model discloses a leakage current test box, which comprises an insulating box body, the insulating box body is provided with a first test terminal, a second test terminal, a third test terminal and a fourth test terminal, the first test terminal and the second test terminal The terminals are used to connect the product to be tested, and the third test terminal and the fourth test terminal are used to output voltage signals to the oscilloscope respectively; in the insulating box, the first test terminal simulates the impedance of the skin and the impedance of the human body in turn, and then connects with the The second test terminal is electrically connected; the two ends that simulate the impedance inside the human body lead out the voltage signal to the third test terminal; one end that simulates the impedance inside the human body also pulls out a wire, which is connected in series with the first resistor and the first capacitor in sequence Afterwards, it is electrically connected with the other end simulating the impedance inside the human body, and a voltage signal is drawn from both ends of the first capacitor to the fourth test terminal. The utility model is easy to operate, easy to connect to the oscilloscope, the whole leakage voltage test value is accurate and precise, and the test process is safe and reliable.

Description

A leakage current test box

technical field

The utility model relates to the technical field of electrical equipment safety detection, in particular to a leakage current test box. the

Background technique

Electric injury, commonly known as electric shock, refers to a systemic and local injury caused by a certain amount of current or electric energy passing through the human body. As electrical equipment is used more and more frequently in life, people know more and more about the causes of electric shock. Therefore, when using electrical equipment, people know more and more how to use electricity safely. However, due to some electrical equipment The electric shock phenomenon caused by its own defects is difficult to avoid, so it is particularly important to detect the electric shock prevention safety of electrical equipment. In most people's minds, electrical equipment insulators are non-conductive, but in fact there are almost no insulating materials that are absolutely non-conductive. Any kind of insulating material, when a voltage is applied across its two ends, there will always be a certain current passing through. The active component of this current is called leakage current, and this phenomenon is also called leakage of the insulator. The so-called leakage current refers to the current formed by the surrounding medium or insulating surface between the metal parts of electrical products that are insulated from each other, or between the live parts and the grounding parts, through the surrounding medium or insulating surface when there is no fault applied voltage. The leakage current of electrical appliances evaluates the insulation performance of a circuit or a system, and is the main indicator of product safety performance. This kind of leakage current is the so-called contact leakage current in the safety test. If the leakage current is not within the safe range, the user will be in danger of electric shock if he touches the outer shell of the product during daily use and operation. This is because The leakage current of the product forms a loop through the human body and the ground, causing electric shock hazard. the

Continuing, in order to avoid the danger of electric shock to the human body, the leakage current of the product must be taken into account in product design. Therefore, it is very important to test the leakage current of electrical products. In the prior art, the leakage current test method of electrical equipment is usually tested by an oscilloscope or a multimeter, and utilizes a simple test circuit simulating the impedance of the human body to test. Second, the test value of the entire leakage voltage is not accurate enough; third, the test process is not safe and reliable enough. the

Utility model content

The technical problem to be solved by the utility model is to provide a leakage current test box for the above-mentioned deficiencies in the prior art. The leakage current test box is more convenient to operate and easy to connect to an oscilloscope. The process is safe and reliable. the

In order to solve the above technical problems, the technical solution of the utility model is: a leakage current test box, including an insulating box body, one end of the insulating box body is provided with a first test terminal and a second test terminal, and the other end of the insulating box body is provided with a second test terminal. Three test terminals and a fourth test terminal, the first test terminal and the second test terminal are used to connect the test position of the product to be tested, and the third test terminal and the fourth test terminal are respectively used to output voltage signals to the oscilloscope; In the insulating box, the first test terminal is electrically connected to the second test terminal after simulating the impedance of the skin and the internal impedance of the human body in sequence; the voltage signals are drawn from both ends of the simulated internal impedance of the human body to the third Test terminal; one end of the simulated internal impedance of the human body also pulls out a lead, which is sequentially connected in series with the first resistor and the first capacitor, and is electrically connected to the other end of the simulated internal impedance of the human body. Voltage signals are drawn from both ends to the fourth test terminal. the

The first test terminal and the second test terminal are respectively connected with wires with alligator clips. the

The third test terminal and the fourth test terminal respectively have an oscilloscope socket for plugging in an oscilloscope. the

The insulating box body includes an upper shell and a lower shell, and the upper shell and the lower shell are fixedly connected by screws. the

The resistance value of the first resistor is 10KΩ, the capacitance value of the first capacitor is 0.022μF; the impedance of the simulated skin is formed by the parallel connection of the second resistor and the second capacitor, and the resistance value of the second resistor is 1.5 KΩ, the capacitance of the second capacitor is 0.22 μF; the impedance inside the simulated human body is the third resistor, and the resistance of the third resistor is 500Ω. the

The beneficial effects of the utility model are: firstly, the first test terminal and the second test terminal can be conveniently connected to the test position of the product to be tested, and the third test terminal and the fourth test terminal can output voltage signals to the oscilloscope conveniently, and the operation Convenient and easy to connect to the oscilloscope; second, in the insulating box, by setting the impedance of the simulated skin and the impedance of the human body, the test value of the entire leakage voltage is accurate and precise; third, the test network is completely enclosed in the insulating shell , the testing process is safer and more reliable. the

Description of drawings

Fig. 1 is a schematic diagram of the overall structure (front) of the present utility model. the

Figure 2 is a schematic diagram of the overall structure (reverse side) of the utility model. the

Fig. 3 is a circuit structure diagram of the utility model. the

In the figure: 1. Insulation box; 11. Upper case; 12. Lower case; 13. Screw; 2. First test terminal; 3. Second test terminal; 4. Third test terminal; 5. Fourth test terminal 6. Wires with alligator clips. the

Detailed ways

Below in conjunction with accompanying drawing, structural principle and working principle of the present utility model are described in further detail. the

As shown in Figures 1 and 2, the utility model is a leakage current test box, which includes an insulating box body 1, one end of the insulating box body 1 is provided with a first test terminal 2 and a second test terminal 3, and the other end of the insulating box body 1 One end is provided with a third test terminal 4 and a fourth test terminal 5, the first test terminal 2 and the second test terminal 3 are used to connect the test position of the product to be tested (not shown in the figure), the third test The terminal 4 and the fourth test terminal 5 are respectively used to output voltage signals to an oscilloscope (not shown in the figure); in the insulating box 1, the first test terminal 2 sequentially simulates the impedance of the skin and the impedance of the human body. After that, it is electrically connected with the second test terminal 3; the two ends of the simulated internal impedance of the human body lead out a voltage signal to the third test terminal 4; one end of the simulated internal impedance of the human body also pulls out a wire, which in turn After the first resistor R ₁ and the first capacitor C ₁ are connected in series, they are electrically connected to the other end simulating the impedance inside the human body, and the voltage signal is drawn from both ends of the first capacitor C ₁ to the fourth test terminal 5 .

In the above technical solution, the first test terminal 2 and the second test terminal 3 are respectively connected with wires 6 with alligator clips, so as to more conveniently clamp the test position of the product to be tested. The third test terminal 4 and the fourth test terminal 5 respectively have an oscilloscope socket for plugging in an oscilloscope. The insulating box body 1 includes an upper shell 11 and a lower shell 12 , and the upper shell 11 and the lower shell 12 are fixedly connected by screws 13 . the

In the above technical solution, the resistance value of the first resistor R ₁ is 10KΩ, and the capacitance value of the first capacitor C ₁ is 0.022 μF; the impedance of the simulated skin is composed of the second resistor R _S and the second capacitor C _S are connected in parallel, the resistance value of the second resistor R _S is 1.5KΩ, the capacitance value of the second capacitor C _S is 0.22μF; the impedance inside the simulated human body is the third resistor R _B , the third resistor The resistance of R _B is 500Ω.

The operating principle of the utility model is: (1) connect the first test terminal 2 to the ground terminal of the product under test, and connect the second test terminal 3 to the shell or output terminal of the product under test; (2) connect the third test terminal 4 and the fourth test terminal 5 are respectively connected to an oscilloscope; (3) connect the product to be tested to the power supply and start it up, and detect the voltage signals output by the third test terminal 4 and the fourth test terminal 5 through an oscilloscope; (4) test the The voltage value of the third test terminal and the voltage value of the fourth test terminal are divided by 500Ω respectively to obtain the DC leakage current and AC leakage current of the product under test. Generally, the DC leakage current limit obtained from the third test terminal is 2.0mA, and the AC leakage current limit from the fourth test terminal is 0.7mA. the

The above is only a preferred embodiment of the utility model, and any minor modifications, equivalent changes and modifications made to the above embodiments according to the technical solution of the utility model all belong to the scope of the technical solution of the utility model. the

Claims (5)

1. A leakage current test box, characterized in that: it comprises an insulating box body, one end of the insulating box body is provided with a first test terminal and a second test terminal, and the other end of the insulating box body is provided with a third test terminal and a fourth test terminal , the first test terminal and the second test terminal are used to connect the test position of the product to be tested, and the third test terminal and the fourth test terminal are respectively used to output voltage signals to the oscilloscope; in the insulating box, the first test terminal A test terminal is electrically connected to the second test terminal after simulating the impedance of the skin and simulating the impedance inside the human body in turn; the two ends of the simulated impedance inside the human body lead out voltage signals to the third test terminal; One end of the impedance also pulls out a wire, which is connected in series with the first resistor and the first capacitor in series, and is electrically connected to the other end of the impedance simulated inside the human body, and the voltage signal is drawn from both ends of the first capacitor to the fourth Test terminals. 2 . The leakage current test box according to claim 1 , wherein the first test terminal and the second test terminal are respectively connected with wires having alligator clips. 3 . 3 . The leakage current test box according to claim 1 , wherein the third test terminal and the fourth test terminal respectively have an oscilloscope socket for plugging in an oscilloscope. 4 . 4. The leakage current test box according to claim 1, wherein the insulating box body comprises an upper case and a lower case, and the upper case and the lower case are fixedly connected by screws. 5. The leakage current test box according to claim 1, characterized in that: the resistance value of the first resistor is 10KΩ, the capacitance value of the first capacitor is 0.022μF; the impedance of the simulated skin is determined by the second A resistor and a second capacitor are connected in parallel, the resistance of the second resistor is 1.5KΩ, and the capacitance of the second capacitor is 0.22μF; the impedance inside the simulated human body is a third resistor, and the resistance of the third resistor The value is 500Ω.