A multifunctional component testing device, system and testing method

Abstract

The application discloses a multifunctional component testing device, system and testing method. The testing device comprises a plurality of testing units. Each testing unit comprises six single-pole double-throw switches, a single-pole single-throw switch and a current and voltage detection module. Two fixed terminals of the first single-pole double-throw switch and the second single-pole double-throw switch are respectively connected with series voltage or parallel voltage. The moving terminals of the third single-pole double-throw switch and the fourth single-pole double-throw switch are connected with two ends of a component to be tested. Two fixed terminals of the fifth single-pole double-throw switch and the sixth single-pole double-throw switch are respectively connected with open circuit or a testing interface. The two ends of the single-pole single-throw switch are respectively connected with the moving terminals of the first single-pole double-throw switch and the second single-pole double-throw switch. The first fixed terminals of the third single-pole double-throw switch and the fourth single-pole double-throw switch are connected with the two ends of the single-pole double-throw switch. The application can test different types of components by using the same device or system, and can be widely applied in the technical field of electronic equipment production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic equipment production, and in particular to a multifunctional component testing device, system and testing method. BACKGROUND

[0002] Inductors and resistors are common components in integrated circuit boards, but in production and use, there are often problems of yield and service life, and the performance of inductors and resistors needs to be tested. However, the testing principles and conditions of inductors and resistors are different, and different test lines are generally used, which is relatively high in cost. In addition, small-scale manual measurement is still used in many factories, that is, workers manually power the inductors or resistors, and then measure them at intervals. This measurement is small in scale and cannot meet the requirements of large-scale testing, and it is also impossible to monitor which line has a fault in time. SUMMARY

[0003] Therefore, the embodiments of the present application provide a multifunctional component testing device, system and testing method, which can test different types of components by using the same device or system and realize large-scale and automatic testing.

[0004] In a first aspect, the embodiments of the present application provide a multifunctional component testing device, which comprises a plurality of testing units, each testing unit comprising a first single-pole double-throw switch, a second single-pole double-throw switch, a third single-pole double-throw switch, a fourth single-pole double-throw switch, a fifth single-pole double-throw switch, a sixth single-pole double-throw switch, a single-pole single-throw switch and a current-voltage detection module, a first fixed terminal of the first single-pole double-throw switch and the second single-pole double-throw switch is connected to a parallel voltage, a second fixed terminal of the first single-pole double-throw switch and the second single-pole double-throw switch is connected to a series voltage, a movable terminal of the third single-pole double-throw switch and the fourth single-pole double-throw switch is connected to two ends of a component to be tested, a first fixed terminal of the fifth single-pole double-throw switch and the sixth single-pole double-throw switch is open, a second fixed terminal of the fifth single-pole double-throw switch and the sixth single-pole double-throw switch is connected to a test interface, two ends of the single-pole single-throw switch are connected to a movable terminal of the first single-pole double-throw switch and a movable terminal of the second single-pole double-throw switch respectively, a first fixed terminal of the third single-pole double-throw switch is connected to a movable terminal of the first single-pole double-throw switch, a first fixed terminal of the fourth single-pole double-throw switch is connected to a movable terminal of the second single-pole double-throw switch, and the current-voltage detection module is connected to a movable terminal of the first single-pole double-throw switch and a first fixed terminal of the second single-pole double-throw switch.

[0005] Optionally, the device comprises a plurality of parallelly connected testing sub-modules, each testing sub-module comprising a plurality of seriesly connected testing units.

[0006] Optionally, the device further comprises a matrix circuit module, the matrix circuit module comprises a plurality of input ports and a plurality of output ports, the input ports and the output ports are connected through a matrix cable, the input ports are connected to the signals to be tested, and the output ports are connected to a testing instrument.

[0007] In a second aspect, the embodiments of the present application provide a multifunctional component testing system, comprising a test board, a temperature box, a power supply, a computer device, and the device described above, the test board is connected to the test interface, and the computer device is connected to the device; wherein the power supply provides power for the testing system; the test board is used for installing the component to be tested; and the temperature box is used for placing the component to be tested.

[0008] In a third aspect, the embodiments of the present application provide a testing method of a multifunctional component testing system, applied to the testing system described above, comprising:

[0009] installing the component to be tested on the test board;

[0010] adjusting the environmental parameters of the temperature box according to a first preset, the environmental parameters comprising temperature and humidity;

[0011] determining the connection of the single-pole double-throw switch and the single-pole single-throw switch in the test unit according to a test item, and setting electrical test parameters according to a second preset; the electrical test parameters comprising current or voltage;

[0012] testing and recording the test signals of the component to be tested.

[0013] Optionally, the test item comprises resistance testing, the connection of the single-pole double-throw switch and the single-pole single-throw switch in the test unit is determined according to the test item, and the method comprises:

[0014] the first single-pole double-throw switch, the second single-pole double-throw switch, the third single-pole double-throw switch, the fourth single-pole double-throw switch, the fifth single-pole double-throw switch, and the sixth single-pole double-throw switch are all closed to a first fixed terminal;

[0015] the single-pole single-throw switch is turned off.

[0016] Optionally, the test item comprises inductance testing, the connection of the single-pole double-throw switch and the single-pole single-throw switch in the test unit is determined according to the test item, and the method comprises:

[0017] the first single-pole double-throw switch and the second single-pole double-throw switch are both closed to a second fixed terminal, and the third single-pole double-throw switch, the fourth single-pole double-throw switch, the fifth single-pole double-throw switch, and the sixth single-pole double-throw switch are all closed to a first fixed terminal;

[0018] the single-pole single-throw switch is turned off.

[0019] Optionally, the method further comprises:

[0020] When the test signal exceeds the preset range, record the failure information and switch the test channel corresponding to the failed component under test.

[0021] Optionally, when the test item is resistance test, the switching process is as follows:

[0022] Close the third single-pole double-throw switch and the fourth single-pole double-throw switch to the second fixed terminal;

[0023] Close the fifth single-pole double-throw switch and the sixth single-pole double-throw switch corresponding to other non-failed components under test to the second fixed terminal.

[0024] Optionally, when the test item is inductance test, the switching process is as follows:

[0025] Close the single-pole single-throw switch;

[0026] Close the third single-pole double-throw switch and the fourth single-pole double-throw switch to the second fixed terminal;

[0027] Close the fifth single-pole double-throw switch and the sixth single-pole double-throw switch corresponding to other non-failed components under test to the second fixed terminal.

[0028] The embodiment of the present application has the following beneficial effects: the multifunctional component testing device in the embodiment includes a plurality of test units, each test unit includes six single-pole double-throw switches, a single-pole single-throw switch, and a current and voltage detection module, the single-pole double-throw switches and the single-pole single-throw switch are connected in a specific manner to form the structure of the testing device, and different test circuits are formed by controlling the opening and closing of the single-pole double-throw switches and the single-pole single-throw switch to test different types of components; the test system includes the multifunctional component testing device and the computer equipment connected to each other, and the computer equipment controls the multifunctional component testing device to realize large-scale and automatic testing of components. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a structural diagram of a test unit in a multifunctional component testing device provided by the embodiment of the present application;

[0030] Figure 2 is a structural diagram of a series connection path for applying voltage;

[0031] Figure 3 is a comparison diagram of normal voltage and abnormal voltage of a series connection path voltage;

[0032] Figure 4 is a structural schematic diagram of a test sub-module provided by an embodiment of the present application;

[0033] Figure 5 is a structural schematic diagram of a multifunctional component test device provided by an embodiment of the present application;

[0034] Figure 6 is a structural schematic diagram of a matrix circuit module provided by an embodiment of the present application;

[0035] Figure 7 is a structural schematic diagram of a multifunctional component test system provided by an embodiment of the present application;

[0036] Figure 8 is a step flow schematic diagram of a test method of a functional component test system provided by an embodiment of the present application;

[0037] Figure 9 is a step flow schematic diagram of another test method of a functional component test system provided by an embodiment of the present application. DETAILED DESCRIPTION

[0038] The present application will be further described in detail below in combination with the drawings and specific embodiments. For the step numbers in the following embodiments, they are only set for the convenience of description and explanation, and the order between the steps is not limited in any way, and the execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0039] In actual testing, for inductance testing, a constant current needs to be applied; if multiple inductances are tested together, the multiple inductances need to be connected in series, and the state of each inductance needs to be monitored; if an open circuit occurs in a certain inductance, the test cannot be performed normally, and the inductance needs to be short-circuited in time to realize the continuity of the current in the entire circuit. For resistance testing, a constant voltage needs to be applied to the resistance; if multiple resistances are tested together, the multiple resistances need to be connected in parallel, and the state of each resistance channel needs to be monitored; if a short circuit occurs in a certain resistance, the test cannot be performed normally, and the resistance needs to be opened in time to realize the constancy of the voltage and ensure the normal performance of the test. Therefore, if the testing of capacitors and inductors needs to be realized in the same system, the system needs to have a transformation capability, can realize the conversion of series and parallel connection according to different components to be tested, has the current and voltage monitoring capability for each component to be tested, and can realize the opening and short-circuiting of the component to be tested when needed.

[0040] As Figure 1As shown, the embodiment of the present application provides a multifunctional component testing device, which comprises a plurality of testing units, each of which comprises a first single-pole double-throw switch S1, a second single-pole double-throw switch S2, a third single-pole double-throw switch S3, a fourth single-pole double-throw switch S4, a fifth single-pole double-throw switch S5, a sixth single-pole double-throw switch S6, a single-pole single-throw switch S7 and a current and voltage detection module, the first fixed terminals 1 of the first single-pole double-throw switch S1 and the second single-pole double-throw switch S2 are connected in parallel with a voltage, the second fixed terminals 2 of the first single-pole double-throw switch S1 and the second single-pole double-throw switch S2 are connected in series with a voltage, the movable terminals of the third single-pole double-throw switch S3 and the fourth single-pole double-throw switch S4 are connected to the two ends of a component to be tested, the first fixed terminals 1 of the fifth single-pole double-throw switch S5 and the sixth single-pole double-throw switch S6 are open, the second fixed terminals 2 of the fifth single-pole double-throw switch S5 and the sixth single-pole double-throw switch S6 are connected to a testing interface, the movable terminals of the single-pole single-throw switch S7 are connected to the movable terminals of the first single-pole double-throw switch S1 and the second single-pole double-throw switch S2 respectively, the first fixed terminals 1 of the third single-pole double-throw switch S3 and the fourth single-pole double-throw switch S4 are connected to the movable terminals of the first single-pole double-throw switch S1 and the second single-pole double-throw switch S2 respectively, and the current and voltage detection module is connected to the movable terminal of the first single-pole double-throw switch S1 and the first fixed terminal 1 of the second single-pole double-throw switch S2.

[0041] Specifically, referring to Table 1, the connection modes of the single-pole double-throw switches and the single-pole single-throw switch in different modes. The testing unit mainly realizes three functions: controlled conversion between series and parallel connection of units, conversion between a testing channel of a component to be tested and a working channel, and controlled opening and short circuit of the component to be tested.

[0042] Table 1

[0043]

[0044] Current monitoring: in parallel mode, the voltage is a constant value, so it is necessary to ensure that each unit in parallel cannot occur short circuit failure, otherwise it will affect the normal testing of the system, each unit of the module has current monitoring and reporting functions, when the current is too large, the protection mechanism will be triggered.

[0045] Voltage monitoring: in series mode, the current is a constant value, it is necessary to ensure that each unit in series cannot occur open circuit failure, otherwise the channel current cannot flow normally, affecting the normal testing of the system, the module monitors the high voltage of each unit, judges the unit that occurs open circuit through algorithm and shorts it, without affecting the normal testing of other units.

[0046] The measured piece is controlled to be open or short: the module can control the measured piece to be open or short, and the measured piece is isolated from the system, which does not affect the test.

[0047] Open circuit monitoring algorithm: for the monitoring of open circuit in series, a ladder scanning algorithm is proposed, which can detect single point open circuit and multi-point open circuit, and accurately locate the open circuit point. In series, refer to Figure 2 Figure 3 , the voltage U is applied at both ends of the series path, then U1-U7 is an approximately linear rising trend, and when one of them is open, the voltage on one side is pulled to the same as U, and the other end is at the same level as the ground. At this time, it can be judged that the point with the largest voltage difference is the open circuit fault point; if the point with the largest voltage difference contains more than one unit (voltage detection point), it means that there is more than one open circuit point in the series path. At this time, according to the ladder scanning mode, short circuit from the side with voltage U is performed in turn, and the open circuit point is recorded. After each short circuit, the voltage of each point is measured again and compared and calculated to determine whether the next unit is in open circuit state. After several rounds of scanning, each open circuit point can be determined.

[0048] Optionally, the device comprises a plurality of parallelly connected test sub-modules, each of which comprises a plurality of series-connected test units.

[0049] Specifically, referring to Figure 4 , the test sub-module comprises a plurality of series-connected test units, the series power supply of adjacent test units is connected in series, and the parallel power supply of different test units is connected to the same voltage.

[0050] Referring to Figure 5 , in a specific embodiment, each test sub-module comprises 8 series-connected test units, and 10 test sub-modules are connected in parallel to form the test device.

[0051] Optionally, the device further comprises a matrix circuit module, the matrix circuit module comprises a plurality of input ports and a plurality of output ports, the input ports and the output ports are connected through a matrix cable, the input ports are connected to the signals to be tested, and the output ports are connected to the test instruments.

[0052] Referring to Figure 6 , in a specific embodiment, the input ports are 30: X1-X30, and the output ports are 4: V1-V4, V1-V4 are respectively connected to DMM1 (digital multimeter), DMM1, LRC1 measuring instrument and LRC2 measuring instrument. Using a large-scale matrix, the function of routing the measured piece in the test state to the interface of any test instrument to test its parameters is realized, and the instrument is multiplexed.

[0053] The implementation of the embodiment of the present application has the following beneficial effects: the multifunctional component testing device in the embodiment includes a plurality of testing units, each testing unit includes six single-pole double-throw switches, one single-pole single-throw switch and one current and voltage detection module, the single-pole double-throw switches and the single-pole single-throw switch are connected in a specific manner to form the structure of the testing device, and different test circuits are formed by controlling the opening and closing of the single-pole double-throw switches and the single-pole single-throw switch to test different types of components.

[0054] The embodiment of the present application provides a multifunctional component testing system, which comprises a test board, a temperature box, a power supply, a computer device and the device.

[0055] Referring to Figure 7 In a specific embodiment, the test board is placed in the temperature box, the temperature box can set temperature and humidity, etc., the test board is connected with the testing unit in the testing device through a clamp, etc., the matrix circuit module is connected with the testing unit and the current and voltage testing module, and the testing unit and the matrix circuit module are connected with the computer device.

[0056] It should be noted that the computer device includes but is not limited to a desktop computer, a tablet computer or a smart phone terminal, etc., and the computer device has a man-machine interactive interface such as a display screen.

[0057] It should be noted that the system can be applied to the quality department of an electronic product to test the aging of inductance and resistance, accelerate the aging process of inductance and resistance under the condition of heating, humidifying and continuous power supply, record the time of aging failure of the capacitor, and use the time as a basis for evaluating the quality of a batch of raw materials.

[0058] The implementation of the embodiment of the present application has the following beneficial effects: the multifunctional component testing device in the embodiment includes a plurality of testing units, each testing unit includes six single-pole double-throw switches, one single-pole single-throw switch and one current and voltage detection module, the single-pole double-throw switches and the single-pole single-throw switch are connected in a specific manner to form the structure of the testing device, and different test circuits are formed by controlling the opening and closing of the single-pole double-throw switches and the single-pole single-throw switch to test different types of components; the testing system includes the multifunctional component testing device and the computer device connected with each other, and the computer device controls the multifunctional component testing device to realize large-scale and automatic testing of components.

[0059] Referring to Figure 8 The embodiment of the present application provides a testing method of a multifunctional component testing system, which is applied to the testing system and comprises the following steps.

[0060] S100, mounting the measured component on the test board;

[0061] S200, adjusting the environmental parameters of the oven according to the first preset, the environmental parameters including temperature and humidity;

[0062] S300, determining the connection of the single-pole double-throw switch and the single-pole single-throw switch in the test unit according to the test item, and setting the electrical test parameters according to the second preset; the electrical test parameters including current or voltage;

[0063] S400, testing and recording the test signal of the measured component.

[0064] Specifically, by placing the measured component into the environmental box, applying the corresponding voltage and current, starting to monitor the electrical parameters of the measured component, ensuring the normal test, and through the matrix system and the deformable test module, the measured component is switched from the working state to the test state in turn, and the measured component is routed to the LRC tester through the external matrix to scan the detailed health status of each measured component, and the data is recorded.

[0065] Referring to Figure 9 After the measured component is placed in the oven, the temperature and humidity are adjusted, and then the current or voltage is applied, and the current or voltage is monitored, when the current or voltage exceeds the set limit, the computer device records the failure time and removes the failure channel, each channel is switched from the working state to the test state in turn, and the test signal result is tested and recorded.

[0066] Optionally, the test item includes resistance test, according to the test item, the connection of the single-pole double-throw switch and the single-pole single-throw switch in the test unit is determined, including:

[0067] The first single-pole double-throw switch, the second single-pole double-throw switch, the third single-pole double-throw switch, the fourth single-pole double-throw switch, the fifth single-pole double-throw switch, and the sixth single-pole double-throw switch are all closed to the first fixed end;

[0068] The single-pole single-throw switch is turned off.

[0069] Specifically, the test principle of resistance is: a batch of resistors are placed in the set test environment, such as 85℃ and 85% humidity environment (double 85), a standard voltage conforming to the rated value of the resistor is applied to the resistor, and the resistance value is monitored to determine whether the resistor is failed, if the resistance value is obviously larger or smaller, it represents failure. If you want to use the same power supply to supply power to multiple resistors at the same time, you need to connect the resistors in parallel, and any one of the resistors cannot be short-circuited, otherwise the power supply will be short-circuited and the test cannot be performed.

[0070] Optionally, the test item includes an inductance test, the connection of the single-pole double-throw switch and the single-pole single-throw switch in the test unit is determined according to the test item, and the test unit comprises:

[0071] The first single-pole double-throw switch and the second single-pole double-throw switch are both closed to the second fixed terminal, and the third single-pole double-throw switch, the fourth single-pole double-throw switch, the fifth single-pole double-throw switch and the sixth single-pole double-throw switch are all closed to the first fixed terminal.

[0072] The single-pole single-throw switch is opened.

[0073] Specifically, the test principle of the inductance is as follows: a batch of inductances are placed in a set test environment, i.e., an environment with a temperature of 85°C and a humidity of 85% (double 85), a standard current conforming to the rated value of the inductance is applied to the inductance, and whether the inductance is failed is determined by monitoring the resistance value of the inductance. If the resistance value is obviously increased or decreased, it means that the inductance is failed. If the same power supply is used to supply power to multiple inductances, all the inductances need to be connected in series, and any one of the inductances cannot be opened, otherwise the test cannot be performed.

[0074] Optionally, the method further comprises:

[0075] When the test signal exceeds the preset range, the failure information is recorded, and the test channel corresponding to the failed measured component is switched.

[0076] Optionally, when the test item is a resistance test, the switching process is as follows:

[0077] The third single-pole double-throw switch and the fourth single-pole double-throw switch are both closed to the second fixed terminal.

[0078] The fifth single-pole double-throw switch and the sixth single-pole double-throw switch corresponding to other non-failed measured components are both closed to the second fixed terminal.

[0079] In one specific embodiment, referring to the test unit in Figure 1 , the S1 and S2 are closed to 1, the S3 and S4 are closed to 1, the parallel mode is entered, the voltage is applied to the parallel power supply end through the program-controlled power supply, the current value of the voltage and current detection module is tested, and when the current value exceeds the threshold value, the S3 and S4 are closed to 2, and the measured component is cut off from the working loop. During the test, each unit is operated in sequence, the S3 and S4 are closed to 2, the S5 and S6 are closed to 2, the test interface is connected to the matrix, and the measured component is tested through the instrument.

[0080] Optionally, when the test item is an inductance test, the switching process is as follows:

[0081] The single-pole single-throw switch is closed.

[0082] The third single-pole double-throw switch and the fourth single-pole double-throw switch are both closed to the second fixed terminal;

[0083] The fifth single-pole double-throw switch and the sixth single-pole double-throw switch corresponding to the other non-failed measured components are both closed to the second fixed terminal.

[0084] In one specific embodiment, referring to the test unit in Figure 1 , access the device to be tested, close S1, S2 to 2, S3, S4 to 1, enter the series mode, apply voltage to the series power supply terminal through the program-controlled power supply, test the voltage value of the voltage and current detection module, and according to the circuit detection algorithm, when a certain point circuit is detected, close S7, at this time the device to be tested is short-circuited, close S3, S4 to 2, and cut off the device to be tested from the working loop. During the test, operate each unit in sequence, close S7, close S3, S4 to 2, close S5, S6 to 2, access the matrix through the test interface, and test the device to be tested through the instrument.

Claims

1. A test method for a multi-functional component test system, characterized by, The multifunctional component testing system comprises a testing board, a temperature box, a power supply, a computer device and a testing device, wherein the testing device comprises a plurality of testing units, each testing unit comprises a first single-pole double-throw switch, a second single-pole double-throw switch, a third single-pole double-throw switch, a fourth single-pole double-throw switch, a fifth single-pole double-throw switch, a sixth single-pole double-throw switch, a single-pole single-throw switch and a current-voltage detection module, the first fixed terminals of the first single-pole double-throw switch and the second single-pole double-throw switch are connected in parallel with a voltage, the second fixed terminals of the first single-pole double-throw switch and the second single-pole double-throw switch are connected in series with a voltage, the movable terminals of the third single-pole double-throw switch and the fourth single-pole double-throw switch are connected to the two ends of a component to be tested, the first fixed terminals of the fifth single-pole double-throw switch and the sixth single-pole double-throw switch are open, the second fixed terminals of the fifth single-pole double-throw switch and the sixth single-pole double-throw switch are connected to a testing interface, the two ends of the single-pole single-throw switch are connected to the movable terminals of the first single-pole double-throw switch and the second single-pole double-throw switch respectively, the first fixed terminals of the third single-pole double-throw switch and the fourth single-pole double-throw switch are connected to the movable terminals of the first single-pole double-throw switch and the second single-pole double-throw switch respectively, the current-voltage detection module is connected to the movable terminal of the first single-pole double-throw switch and the first fixed terminal of the second single-pole double-throw switch, the testing board is connected to the testing interface, and the computer device is connected to the testing device; wherein the power supply provides power for the testing system, the testing board is used for mounting the component to be tested, and the temperature box is used for placing the component to be tested. The component to be tested is mounted on the testing board; The environmental parameters of the temperature box are adjusted according to a first preset, and the environmental parameters include temperature and humidity; The connections of the single-pole double-throw switches and the single-pole single-throw switch in the testing unit are determined according to a test item, and electrical testing parameters are set according to a second preset; the electrical testing parameters include current or voltage; The test signals of the component to be tested are tested and recorded; The test item includes resistance testing, the connections of the single-pole double-throw switches and the single-pole single-throw switch in the testing unit are determined according to the test item, and the test item includes: The first single-pole double-throw switch, the second single-pole double-throw switch, the third single-pole double-throw switch, the fourth single-pole double-throw switch, the fifth single-pole double-throw switch and the sixth single-pole double-throw switch are all closed to the first fixed terminals; The single-pole single-throw switch is opened.

2. The test method of claim 1, wherein, The test item includes inductance testing, the connections of the single-pole double-throw switches and the single-pole single-throw switch in the testing unit are determined according to the test item, and the test item includes: The first single-pole double-throw switch and the second single-pole double-throw switch are both closed to the second fixed terminals, and the third single-pole double-throw switch, the fourth single-pole double-throw switch, the fifth single-pole double-throw switch and the sixth single-pole double-throw switch are all closed to the first fixed terminals; The single-pole single-throw switch is opened.

3. The test method according to any one of claims 1-2, characterized in that, The method further comprises: When the test signals exceed a preset range, failure information is recorded and the test channel corresponding to the failed component to be tested is switched.

4. The test method of claim 3, wherein, When the test item is resistance test, the switching process is as follows: Close the third single-pole double-throw switch and the fourth single-pole double-throw switch to the second fixed terminal; Close the fifth single-pole double-throw switch and the sixth single-pole double-throw switch corresponding to other non-failed components to be tested to the second fixed terminal.

5. The test method of claim 3, wherein, When the test item is inductance test, the switching process is as follows: Close the single-pole single-throw switch; Close the third single-pole double-throw switch and the fourth single-pole double-throw switch to the second fixed terminal; Close the fifth single-pole double-throw switch and the sixth single-pole double-throw switch corresponding to other non-failed components to be tested to the second fixed terminal.

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