Leakage current test tool

Abstract

The utility model relates to a leakage current test tool, which is a box body and comprises a front panel, a rear panel and a box interior, a power-on switch, a safety emergency stop switch, a circuit breaker II, a circuit breaker III, a three-phase change-over switch, a single-phase change-over switch and a three-phase starting button switch are arranged on the front panel; a control power supply incoming line interface, a main loop input terminal strip, a main loop output terminal strip I, a main loop output terminal strip II and a circuit breaker I are arranged on the rear panel; a contactor I, a contactor II, a contact current MD test box and a switching power supply are arranged in the box. According to the utility model, the technical problems of complicated manual operation test process, low efficiency and insufficient accuracy in the prior art are solved.

Description

Technical Field

[0001] This application belongs to the technical field of inductive components, and particularly relates to a leakage current test tooling. Background Art

[0002] In the prior art, as an important part of medical equipment, the safety and reliability of the medical power distribution unit directly affect the overall performance and stable operation of the equipment. Traditionally, the medical power distribution unit needs to undergo a number of strict tests before leaving the factory to ensure that its quality meets the relevant standards. Among them, the leakage current test and the open-phase fault test are key links for detecting whether there are electrical safety hazards during the use of the equipment. However, the existing test methods usually have many problems, mainly manifested in the following aspects:

[0003] Low efficiency: Most of the existing test methods are manual operations, the test process is complex, time-consuming, and difficult to adapt to the fast pace of modern production. Especially in a mass production environment, manual operations are likely to result in the test speed being unable to keep up with the requirements of the production line, thus affecting the factory efficiency.

[0004] Insufficient accuracy: Manual testing is limited by human factors, and small errors in the operation process may lead to inaccurate test results. In addition, equipment aging or operator negligence will also affect the detection accuracy, increasing the possibility of missed detection and misjudgment.

[0005] Difficult to meet the requirements of modern production: With the rapid development of medical equipment technology, the design and functions of the power distribution unit are becoming more and more complex. Traditional test methods often cannot meet the increasing requirements for test accuracy and reliability. Especially when facing products with high performance and high safety standards, the limitations of existing test means are more obvious.

[0006] In order to improve the test efficiency, enhance the accuracy, and better meet the requirements of modern production, there is an urgent need for a special test tooling that can automatically perform leakage current and open-phase fault tests to ensure that the equipment can undergo more strict quality control before leaving the factory and prevent defective products from entering the market. Summary of the Utility Model

[0007] In view of the deficiencies in the related art, the present utility model provides a leakage current test tooling, which solves the technical problems of complex, inefficient, and inaccurate manual operation in the existing technology.

[0008] In a possible implementation, a leakage current test tooling is provided. The test tooling is a box body, including: a front panel, a rear panel, and the interior of the box; on the front panel, there are provided: a power-on switch (F), an emergency stop switch (SB), a circuit breaker II (Q2), a circuit breaker III (Q3), a three-phase changeover switch (SB4), a single-phase changeover switch (SB5), and three-phase start button switches (SB1 / SB2 / SB3); on the rear panel, there are provided: a control power supply incoming line interface (LN / PE), a main circuit input terminal block (U / V / W / N / PE), a main circuit output terminal block I (U / V / W), a main circuit output terminal block II (L / N), and a circuit breaker I (Q1); inside the box, there are provided: contactors I (KM1 / KM2 / KM3) and contactors II (KM4 / KM5), a touch current MD test box, and a switching power supply (AD); among them, one end of the power-on switch (F) is connected to the L terminal of the control power supply incoming line port, and the other end is connected to the L terminal and N terminal of the switching power supply (AD); the L terminal of the control power supply incoming line port is connected to the control loop input voltage; the emergency stop switch (SB) is connected between the N terminal of the control power supply incoming line port and the N terminal of the switching power supply (AD); between the two output terminals of the switching power supply (AD), branches in which the three sub-switches of the three-phase start button switches (SB1 / SB2 / SB3) are respectively connected in series with the three coils (km1 / km2 / km3) of the contactors I (KM1 / KM2 / KM3) are connected in parallel; after the three-phase changeover switch (SB4) and the single-phase changeover switch (SB5) are respectively connected in parallel with the two sub-switches of the contactors II (KM4 / KM5) and then with KM4 and KM5, they are respectively connected in series with the sub-coils (km4) and sub-coils (km5) of the contactors II (KM4 / KM5) and then connected in parallel between the two output terminals of the switching power supply (AD); the three-phase changeover switch (SB4) and the single-phase changeover switch (SB5) are interlock switches; the U / V / W terminals of the main circuit input terminal block (U / V / W / N / PE) are connected to the main circuit output terminal block I (U / V / W) through the circuit breaker I (Q1) and the three sub-switches of the contactors I (KM1 / KM2 / KM3); the N terminal of the main circuit input terminal block (U / V / W / N / PE) is connected to the N terminal of the main circuit output terminal block II (L / N) through the circuit breaker II (Q2) and the two parallel sub-switches KM4 and KM5 of the contactors II (KM4 / KM5); the L terminal of the main circuit output terminal block II (L / N) is sequentially connected to the W terminal of the main circuit input terminal block (U / V / W / N / PE) through the two parallel sub-switches KM4 and KM5 of the contactors II (KM4 / KM5), the circuit breaker III (Q3), and the circuit breaker I (Q1); the PE terminal of the main circuit input terminal block (U / V / W / N / PE) is connected to the B terminal of the touch current MD test box; the A terminal of the touch current MD test box is connected to the grounding copper bar of the product to be tested.

[0009] In a possible implementation, the U terminal and B terminal of the touch current MD test box are connected to a millivolt-level voltmeter.

[0010] In a possible implementation, the power-on indicator light (L) is connected between the power-on switch (F) and the safety emergency stop switch (SB).

[0011] In a possible implementation, the power-on indicator light (L) is arranged on the front panel.

[0012] In a possible implementation, the L terminal of the control power inlet is connected to the input voltage of the control circuit, 220V / 50Hz.

[0013] In a possible implementation, the main circuit output terminal block Ⅰ (U / V / W) and the main circuit output terminal block Ⅱ (L / N) are respectively connected to the three-phase power product to be tested and the single-phase power product to be tested.

[0014] In a possible implementation, the main circuit input terminal block (U / V / W / N / PE) is connected to the variable frequency power supply.

[0015] Based on the above technical solutions, for the leakage current test tooling of the present utility model, after being powered on, the tooling provides voltage to the test circuit through the control circuit. The user can select a three-phase or single-phase circuit through the changeover switch; Contactor I and Contactor II respectively control the conduction and disconnection of the three-phase and single-phase test circuits. The leakage current is collected through the touch current MD test box and transmitted to the display device in real time; When the current exceeds the set value, the system gives an alarm to ensure the safety during the test process; The test efficiency and accuracy are improved, and the reliability of the equipment safety detection is ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the present utility model and constitute a part of this application. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0017] Figure 1 It is a schematic diagram of the front panel structure of the leakage current test tooling of an embodiment of the present utility model;

[0018] Figure 2 It is a schematic diagram of the rear panel structure of the leakage current test tooling of an embodiment of the present utility model;

[0019] Figure 3 It is a schematic diagram of the internal structure of the box of the leakage current test tooling of an embodiment of the present utility model;

[0020] Figure 4 It is a schematic diagram of the internal structure of the box of the leakage current test tooling of another embodiment of the present utility model;

[0021] Figure 5This is the electrical connection diagram of the leakage current test tooling for another embodiment of the present utility model.

[0022] In the figure:

[0023] 1. Front panel; 2. Rear panel; 3. Power-on indicator light; 4. Power-on switch; 5. Circuit breaker II; 6. Circuit breaker III; 7. Safety emergency stop switch; 8. Three-phase changeover switch; 9. Single-phase changeover switch; 10. Three-phase start button switch; 11. Control power input interface; 12. Main circuit input terminal block; 13. Main circuit output terminal block I; 131. Main circuit output terminal block II; 14. Contactor I; 15. Contactor II; 16. Touch current MD test box; 17. Switching power supply; 18. Circuit breaker I. Specific embodiments

[0024] Next, the technical solutions in the embodiments will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present application.

[0025] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "horizontal", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present application.

[0026] The terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", "third" may explicitly or implicitly include one or more of such features.

[0027] In the description of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the internal connection of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0028] To solve the technical problems of complex manual operation, low efficiency, and insufficient accuracy in the existing technology during the testing process, this application proposes a leakage current testing tooling.

[0029] See Figures 1 - 5 , in a possible implementation, the leakage current testing tooling is a box structure. See Figure 1 , the front panel 1 is provided with a power-on switch 4, a safety emergency stop switch 7, a circuit breaker II 5, a circuit breaker III 6, a three-phase changeover switch 8, a single-phase changeover switch 9, and a three-phase start button switch 10; See Figure 2 , the rear panel 2 is provided with a control power supply incoming line interface 11, a main circuit input terminal block 12, a main circuit output terminal block I 13, a main circuit output terminal block II 131, and a circuit breaker I 18; See Figure 3 and Figure 4 , inside the box, a contactor I 14, a contactor II 15, a touch current MD test box 16, and a switching power supply 17 are arranged;

[0030] See Figure 5 , the power-on switch F1 is connected between the L terminal of the control power supply incoming line interface LN / PE, the L terminal and the N terminal of the switching power supply AD to control the on and off of the control power supply; the safety emergency stop switch SB is connected between the N terminal of the control power supply incoming line interface LN / PE and the N terminal of the switching power supply AD for emergency power-off protection; between the two output terminals of the switching power supply AD, three sub-switches SB1 / SB2 / SB3 of the three-phase start button switch are connected in parallel with the circuits after being respectively connected in series with the three coils km1 / km2 / km3 of the contactor I KM1 / KM2 / KM3 to control the start of the three-phase circuit; the safety emergency stop switch SB adopts LA39-A1-01Z / R;

[0031] The three-phase changeover switch SB4 and the single-phase changeover switch SB5 are interlocked designs, and are respectively connected in parallel with the sub-switches KM4 / KM5 of the contactor II KM4 / KM5. After being connected in parallel, they are respectively connected in series with the sub-coils km4 or km5 of the contactor II KM4 or KM5 on their respective branches, and the normally closed switches km5 or km4 of the contactor II KM5 or KM4 on the other branch. After being connected in series, the two branches are connected to the two output terminals of the switching power supply AD to ensure the interlocked switching between the three-phase and single-phase circuits and prevent simultaneous operation;

[0032] The U, V, and W terminals of the main circuit input terminal block U / V / W / N / PE are connected to the main circuit output terminal block I U / V / W through the circuit breaker I Q1 and the sub-switches of the contactor I KM1 / KM2 / KM3 for the input and output control of the three-phase circuit; the N terminal of the main circuit input terminal block U / V / W / N / PE is connected to the N terminal of the main circuit output terminal block II L / N through the circuit breaker II Q2 and the parallel sub-switches KM4 / KM5 of the contactor II KM4 / KM5.

[0033] The L terminal of the main circuit output terminal block Ⅱ L / N is sequentially connected to the W terminal of the main circuit input terminal block U / V / W / N / PE through the parallel sub-switches KM4 / KM5 of the contactors Ⅱ KM4 / KM5, the circuit breaker Ⅲ Q3, and the circuit breaker Ⅰ Q1; the PE terminal of the main circuit input terminal block U / V / W / N / PE is connected to the B terminal of the touch current MD test box; the A terminal of the touch current MD test box is connected to the grounding copper bar of the product under test for measuring leakage current.

[0034] As a tool for detecting the leakage current of electrical equipment, the leakage current test tooling forms an effectively controllable and monitorable test circuit system by arranging various electrical components on the front and rear panels and inside the test tooling.

[0035] The power-on switch F1, safety emergency stop switch SB, three-phase and single-phase changeover switches SB4 / SB5, and three-phase start buttons SB1 / SB2 / SB3 on the front panel provide flexible operation interfaces, and users can select corresponding operation modes according to actual test requirements. Through the interlocked three-phase and single-phase changeover switches, the occurrence of misoperation is avoided. The contactors Ⅰ KM1 / KM2 / KM3 and contactors Ⅱ KM4 / KM5 inside the box body are used as current control devices to control the three-phase and single-phase current paths respectively, ensuring the on and off of the current in different test modes. The touch current MD test box is used as a monitoring device to accurately measure the leakage current of the device under test.

[0036] Power-on switch F1: Used to control the power-on and power-off states of the entire test tooling to ensure the normal operation of the equipment during testing.

[0037] Safety emergency stop switch SB: Provides the power-off function in case of emergency. When an accident occurs, users can quickly cut off the power supply to ensure the safety of operators.

[0038] Circuit breakers Ⅰ Q1, Ⅱ Q2, Ⅲ Q3: Used to protect the main circuit and control circuit to prevent overcurrent or short-circuit situations.

[0039] Contactors Ⅰ KM1 / KM2 / KM3 and contactors Ⅱ KM4 / KM5: Responsible for controlling the on and off of the current in the three-phase and single-phase circuits.

[0040] Three-phase start buttons SB1 / SB2 / SB3: Connected to the coil of the contactor Ⅰ in parallel to control the start of the three-phase circuit.

[0041] Touch current MD test box: Used to detect the leakage current of the device under test and provide measurement data for operators to refer to.

[0042] When the power switch F1 is closed, the control circuit is energized, the switching power supply AD starts to work, and supplies power to the internal control devices. According to the operation requirements, the user can select the corresponding test mode through the three-phase switching switch SB4 or the single-phase switching switch SB5. When selecting the three-phase test, press the three-phase start buttons SB1 / SB2 / SB3, the coils of the contactors Ⅰ KM1 / KM2 / KM3 are activated, the three-phase circuit is connected, and the U / V / W terminals of the main circuit input terminal block pass through the circuit breaker Ⅰ Q1 and the sub-switch of the contactor Ⅰ, and the current flows to the main circuit output terminal block Ⅰ U / V / W, thus starting the three-phase leakage current test; similarly, when selecting the single-phase test, the contactor Ⅱ (KM4 / KM5) will be connected, and the current passes through the circuit breaker Ⅱ Q2, the circuit breaker Ⅲ Q3 and the contactor Ⅱ, and flows to the main circuit output terminal block Ⅱ L / N to complete the single-phase leakage current test.

[0043] The leakage current test tooling controls the on / off of the main circuit through the switches and circuit breakers on the front panel. During the operation, the power switch F1 first connects the control power supply, starts the switching power supply AD, and provides a low-voltage control signal; in the three-phase mode, the three-phase start button switches SB1, SB2, SB3 respectively control the coils of KM1, KM2, KM3 of the contactor Ⅰ, thus connecting the three-phase current of the main circuit and making the current pass through the U / V / W terminals of the main circuit output terminal block Ⅰ; in the single-phase mode, the single-phase switching switch SB5 controls the sub-coils of KM4 / KM5 of the contactor Ⅱ, thus connecting the single-phase current of the main circuit and making the current pass through the L / N terminals of the main circuit output terminal block Ⅱ; at the same time, the touch current MD test box is used to detect the leakage current, and the test result is read through the connected ammeter or test equipment. Each circuit of the main circuit provides overcurrent protection through the corresponding circuit breaker Ⅰ Q1, circuit breaker Ⅱ Q2, circuit breaker Ⅲ Q3 to ensure the safety of the test process.

[0044] In a possible implementation, the U terminal and the B terminal of the touch current MD test box are connected to a millivolt-level voltmeter, which is used to accurately measure the voltage change of the leakage current; through this voltmeter, the operator can monitor the leakage current of the device under test in real time to ensure the accuracy and precision of the measurement.

[0045] The U terminal and the B terminal of the touch current MD test box detect the leakage current through a millivolt-level voltmeter. When the device under test is running, the leakage current is transmitted to the touch current MD test box through the grounding copper bar, and the meter indirectly measures the magnitude of the leakage current through the voltage change and displays it on the voltmeter.

[0046] In a possible implementation, the power-on indicator light L / power-on indicator light 3 is set on the front panel 1 and is connected between the power switch F1 and the safety emergency stop switch SB5; this indicator light is used to display the power-on state of the device, which is convenient for the operator to quickly confirm whether the device is in the working state and improves the convenience and safety of the operation.

[0047] The power-on indicator light L is connected through a circuit between the power-on switch F1 and the safety emergency stop switch SB. When the power-on switch F1 is turned on, the indicator light L will light up, indicating to the operator that the test fixture is powered on; if the safety emergency stop switch SB is pressed, the indicator light L will go out, indicating that the fixture is powered off.

[0048] In a possible implementation, the L terminal of the control power supply inlet interface LN / PE is connected to the input voltage of the 220V / 50Hz control circuit, ensuring that the fixture has stable power input conditions. This power standard is applicable to most industrial scenarios, ensuring the wide applicability of the equipment.

[0049] The power-on indicator light L is connected to the front panel of the test fixture through a switch circuit. When the fixture is powered on, the indicator light lights up, and the operator can directly observe the power-on state of the fixture from the front panel, thus ensuring the normal progress of the test process.

[0050] In a possible implementation, the main circuit output terminal block ⅠU / V / W and the main circuit output terminal block ⅡL / N are respectively connected to the three-phase electrical product to be tested and the single-phase electrical product to be tested. This design allows the fixture to be applicable to different types of electrical equipment, enhancing the applicable range of the test fixture.

[0051] The L terminal of the control power supply inlet is connected to the 220V / 50Hz mains power supply, providing stable power support for the control circuit of the fixture, thus ensuring the normal operation of each electrical component inside the fixture.

[0052] In a possible implementation, the main circuit input terminal block U / V / W / N / PE is connected to a variable frequency power supply to meet the test requirements under different voltage frequency environments. The use of the variable frequency power supply ensures that the fixture can conduct tests under various power conditions, providing a more flexible test environment.

[0053] The power input of the three-phase product to be tested is connected through the main circuit output terminal block ⅠU / V / W, while the power input of the single-phase product to be tested is connected through the main circuit output terminal block ⅡL / N. The changeover switch and contactor inside the fixture achieve the switching between the three-phase and single-phase modes, so as to be able to conduct leakage current tests on different electrical equipment.

[0054] In a possible implementation, the main circuit input terminal block U / V / W / N / PE is connected to a variable frequency power supply to provide power support at different frequencies.

[0055] The main circuit input terminal block is connected to a variable frequency power supply, which can adjust the frequency of the input power according to the test requirements, so as to test the leakage current situation under different frequency conditions.

[0056] The leakage current test tooling according to an embodiment of the present utility model is specifically described as follows:

[0057] As an important part of electrical equipment, the medical power distribution unit is crucial for the stable operation of the entire system in terms of safety and reliability. To ensure that the product meets the standard requirements before leaving the factory, comprehensive leakage current and single-phase loss fault tests are required. In order to promptly detect and prevent defective products from flowing out, and at the same time improve the traditional testing methods that are inefficient, inaccurate, and difficult to meet the needs of modern production, it is particularly important to design a dedicated test tooling.

[0058] The single-phase loss and leakage current test tooling for cabinet factory testing of the present utility model mainly includes the following parts:

[0059] 1. The test host, i.e., the box structure: includes the touch current MD test box inside the box, with a built-in leakage current test module, single-phase loss fault test module, and display module.

[0060] 2. The test fixture: used to connect the cabinet, collect leakage current signals, and supply power.

[0061] 3. The data transmission module: transmits the test data to the display module or external devices.

[0062] 4. The power module: provides power support for the entire tooling.

[0063] Leakage current test: The leakage current signal of the cabinet is collected through the test fixture, transmitted to the leakage current test module in the test host for analysis, the leakage current value is displayed in real time, and an alarm prompt is given when it exceeds the preset safety value.

[0064] Single-phase loss fault test: The single-phase loss fault test module in the test host monitors the power supply status of the cabinet in real time. When a single-phase loss or abnormality of the power supply is detected, the alarm device is immediately triggered to prompt the maintenance personnel to check and handle.

[0065] Main technical parameters:

[0066] Leakage current detection range: 0.1 mA - 100 A

[0067] Leakage current detection accuracy: ±0.5%

[0068] Single-phase loss fault detection response time: <50 ms

[0069] Display mode: Real-time display on the liquid crystal display screen

[0070] Alarm mode: Sound alarm, light alarm

[0071] Working power supply: AC 380 V ±10%, 50 Hz

[0072] Operating environment: temperature -10°C to +50°C, humidity 20% to 90% RH

[0073] The electrical schematic diagram is as shown in Figure 5 , the main circuit electrical connection and disconnection is controlled by the Q1 / Q2 / Q3 air switches, and the control circuit electrical connection and disconnection is controlled by the SB, F1, and F2 push-button switches. Among them, SB1 / SB2 / SB3 can respectively control the connection and disconnection of three-phase electricity, as well as the connection and disconnection of any one of the phases missing, so as to achieve the purpose of phase loss detection. When the input of the product to be tested is single-phase electricity, the corresponding contactors can be controlled by SB4 / SB5 to achieve the purpose of LN or NL phase conversion test, and the phase L or N can be cut off by turning off Q2 / Q3 to achieve the purpose of phase loss test.

[0074] The phase loss and leakage current test tooling for the factory test of the cabinet of the present utility model has the following beneficial effects:

[0075] 1. Efficient detection: This tooling can quickly and accurately detect the leakage current of the cabinet under normal conditions and in the case of a single phase loss fault, greatly improving the factory test efficiency.

[0076] 2. Simple operation: The tooling is simply designed and has a user-friendly operation interface, which is suitable for large-scale tests on the production line.

[0077] 3. Stable and reliable: High-precision displays and highly reliable test modules are used to ensure the stability and accuracy of the test results.

[0078] 4. Comprehensive detection: It can comprehensively detect various electrical parameters of the cabinet to ensure the quality and safety of the factory products.

[0079] Finally, it should be noted that: the various embodiments in this specification are described in a progressive manner, and the key points of each embodiment are the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0080] The above embodiments are only used to illustrate the technical solutions of the present application and not to limit them; although the present application has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: still can modify the specific implementation manners of the present application or perform equivalent replacements on some technical features; without departing from the spirit of the technical solutions of the present application, they should all be covered within the scope of the technical solutions claimed in the present application.

Claims

1. A leakage current test tooling, characterized in that: The test tooling is a box body, including: a front panel, a rear panel, and the interior of the box; On the front panel are provided: a power-on switch (F), an emergency stop switch (SB), a circuit breaker II (Q2), a circuit breaker III (Q3), a three-phase changeover switch (SB4), a single-phase changeover switch (SB5), and three-phase start button switches (SB1 / SB2 / SB3); On the rear panel are provided: a control power supply incoming line interface (LN / PE), a main circuit input terminal block (U / V / W / N / PE), a main circuit output terminal block I (U / V / W), a main circuit output terminal block II (L / N), and a circuit breaker I (Q1); Inside the box are provided: contactors I (KM1 / KM2 / KM3) and contactors II (KM4 / KM5), a contact current MD test box, and a switching power supply (AD); where One end of the power-on switch (F) is connected to the L terminal of the control power supply incoming line port, and the other end is connected to the L terminal and N terminal of the switching power supply (AD); The L terminal of the control power supply incoming line port is connected to the control circuit input voltage; The emergency stop switch (SB) is connected between the N terminal of the control power supply incoming line port and the N terminal of the switching power supply (AD); Between the two output terminals of the switching power supply (AD), branches in which three sub-switches of the three-phase start button switches (SB1 / SB2 / SB3) are respectively connected in series with three coils (km1 / km2 / km3) of the contactors I (KM1 / KM2 / KM3) in parallel are provided; The three-phase changeover switch (SB4) and the single-phase changeover switch (SB5) are respectively connected in parallel with two sub-switches of the contactors II (KM4 / KM5) and then KM4 and KM5, and then are respectively connected in series with the sub-coils (km4) and sub-coils (km5) of the contactors II (KM4 / KM5), and are connected in parallel between the two output terminals of the switching power supply (AD); the three-phase changeover switch (SB4) and the single-phase changeover switch (SB5) are interlocking switches; The U / V / W terminals of the main circuit input terminal block (U / V / W / N / PE) are connected to the main circuit output terminal block I (U / V / W) through the circuit breaker I (Q1) and three sub-switches of the contactors I (KM1 / KM2 / KM3); the N terminal of the main circuit input terminal block (U / V / W / N / PE) is connected to the N terminal of the main circuit output terminal block II (L / N) through the circuit breaker II (Q2) and two parallel sub-switches KM4 and KM5 of the contactors II (KM4 / KM5); The L terminal of the main circuit output terminal block II (L / N) is sequentially connected to the W terminal of the main circuit input terminal block (U / V / W / N / PE) through two parallel sub-switches KM4 and KM5 of the contactors II (KM4 / KM5), the circuit breaker III (Q3), and the circuit breaker I (Q1); The PE terminal of the main circuit input terminal block (U / V / W / N / PE) is connected to the B terminal of the contact current MD test box; the A terminal of the contact current MD test box is connected to the grounding copper bar of the product to be tested.

2. The leakage current test tooling according to claim 1, wherein The U terminal and B terminal of the contact current MD test box are connected to a millivolt-level voltmeter.

3. The leakage current test tooling according to claim 2, characterized in that, A power-on indicator light (L) is connected between the power-on switch (F) and the emergency stop switch (SB).

4. The leakage current test tooling according to claim 3, wherein, The power-on indicator light (L) is arranged on the front panel.

5. The leakage current test tooling according to claim 4, characterized in that The L terminal of the control power supply inlet is connected to the input voltage of the control circuit, 220V / 50Hz.

6. The leakage current test tooling according to claim 5, characterized in that, The main circuit output terminal block Ⅰ (U / V / W) and the main circuit output terminal block Ⅱ (L / N) are respectively connected to the three-phase power product to be tested and the single-phase power product to be tested.

7. The leakage current test tooling according to claim 6, characterized in that, The main circuit input terminal block (U / V / W / N / PE) is connected to the variable frequency power supply.

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