Multi-harness testing method and system

Abstract

The present invention discloses a multi-wiring harness testing method and system, which relates to the field of wiring harness testing technology and solves the problem of insufficient comprehensiveness of the original testing method. The present invention conducts a compliance test again on the confirmed normal wiring harness, confirms the attenuation rate associated with the corresponding wiring harness based on the signal characteristics of the corresponding wiring harness transmission signal, and locks in whether the corresponding normal wiring harness is a compliance wiring harness or a substandard wiring harness based on the numerical parameters of the attenuation rate. For the substandard wiring harness, a voltage interval is adopted and the internal voltage value of the wiring harness is gradually increased to confirm the current numerical performance associated with the corresponding wiring harness. Based on the specific numerical performance results, it is confirmed whether the corresponding substandard wiring harness will affect normal use in the later stage, thereby improving the overall evaluation effect between the wiring harnesses, ensuring the comprehensiveness of the comprehensive test, and enabling multiple wiring harnesses to obtain effective testing results.

Description

Technical Field

[0001] The present invention relates to the technical field of wire harness testing, and in particular to a multi-wire harness testing method and system. Background Art

[0002] Automated wire harness testers can be used to automatically complete multiple testing tasks by programming test parameters and processes. Automated testing offers advantages such as speed, high accuracy, and good repeatability, making it suitable for testing large-scale, complex wire harness production lines. By placing the wire harness in simulated, actual operating environments, such as high- and low-temperature test chambers, vibration test benches, and electromagnetic shielding chambers, comprehensive performance testing can be performed. This method can more realistically reflect the actual performance of the wire harness, but it requires more sophisticated testing equipment and environments, and is relatively expensive.

[0003] The application with publication number CN110850337A discloses a multi-harness test system, method, device and storage medium. The system includes: a computer device for storing, decomposing, receiving and analyzing test files; the test files include basic data, production data and product test data; a number of harness test equipment for testing the technical parameters of the harness; a number of test boards and / or test fixtures for connecting the harness and the harness test equipment; the computer device is connected to the harness test equipment via a communication interface. In this test system, the computer device and the test equipment are connected via a communication interface, and the test equipment is connected to the harness via a test board and / or test fixture. The test data of the harness test is analyzed to determine whether the test is qualified, thereby achieving simultaneous testing of multiple products or joint testing of multiple test equipment, automatic processing of test data and test results, and high utilization rate of the test equipment, good scalability and high efficiency. This invention can be widely used in the field of harness testing technology.

[0004] During the test process, the wiring harness is evaluated as normal based on the numerical parameter performance of the corresponding wiring harness. However, the original wiring harness processing method does not provide comprehensive test results. During the test, the wiring harness is evaluated as substandard based on the test results. However, such substandard wiring harness does not affect normal use in actual use, so there will be some errors in the test accuracy, and the test is not comprehensive enough. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the present invention provides a multi-harness testing method and system, which solves the problem that the original testing method is not comprehensive enough.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: a multi-harness testing method, comprising the following steps:

[0007] Step 1: Use a preset pulse signal to synchronously test multiple wiring harnesses to identify whether there is a reflected signal at the signal transmitting end. Based on the identification results, locate the faulty wiring harness and the normal wiring harness. Then, based on the waveform difference between the pulse signal and the reflected signal in the abnormal wiring harness, locate the abnormal cause of the faulty wiring harness and display it. The specific method is as follows:

[0008] S11. A preset pulse signal is transmitted from a signal transmitting end to each wiring harness in the multi-wiring harness to identify whether the corresponding wiring harness generates a reflection signal. If a reflection signal is generated, the corresponding wiring harness is marked as a faulty wiring harness; if no reflection signal is generated, the corresponding wiring harness is marked as a normal wiring harness.

[0009] S12. Confirm the signal waveforms of the pulse signal and the reflected signal. Use the starting point of the pulse signal waveform as a calibration point, use the amplitude associated with the calibration point as a reference amplitude, and calibrate it as Jz. Then confirm the specific amplitude associated with the turning point of the internal signal waveform of the reflected signal, and calibrate it as Fz. The waveform segments before and after the turning point have opposite trends. Use: Fz-Jz=Tz to confirm the waveform feature Tz associated with the reflected signal.

[0010] If Tz is less than 0, it means that the reflected signal and the pulse signal are in the opposite state. In this case, a low-resistance signal is directly generated. The time t from the start of pulse signal transmission to the reception of the reflected signal is then confirmed. The distance parameter L1 of the abnormal node is determined using the formula: L1=v×t / 2. v is a preset value representing the transmission speed of the signal within the wiring harness. The generated low-resistance signal and distance parameter L1 are displayed.

[0011] If Tz>0, it means that a reflected signal exists, but it does not present an opposite state to the pulse signal. In this case, an impedance mismatch point presence signal is directly generated. Based on the time t from the start of pulse signal transmission to the reception of the reflected signal, the distance parameter L2 of the abnormal node is determined using the formula: L2=v×t / 2. The generated impedance mismatch point presence signal and distance parameter L2 are displayed.

[0012] Step 2: Based on the normal wiring harness determined within the multi-wiring harness, confirm the received signal associated with the normal wiring harness during the synchronous test from the signal receiving end. Based on the waveform characteristics associated with the received signal, confirm the attenuation rate of the corresponding pulse signal within the corresponding normal wiring harness. Based on the attenuation rate, assess whether the normal wiring harness is a qualified wiring harness. The specific method is as follows:

[0013] S21. Confirm the signal characteristics of the preset pulse signal, lock the amplitude and width associated with the pulse signal, calibrate the confirmed amplitude as Fz, calibrate the horizontal width between the start point and the end point of the pulse signal waveform as Kd, and use: XT = Fz × C1 + Kd × C2 to confirm the signal characteristic XT associated with this pulse signal, where C1 and C2 are preset fixed coefficient factors;

[0014] S22: Using the same processing method as step S21, confirm the signal characteristics of the received signal associated with the normal line bundle, and mark the different signal characteristics confirmed by different normal line bundles as T k , where k represents different normal harnesses, using: XJ k =[(XT-T k )÷XT]×100% Confirm the attenuation rate XJ associated with the corresponding normal harness k , evaluate the attenuation rate XJ associated with the normal harness k Is it satisfied: XJ k ≥20%, otherwise, the normal wiring harness is marked as a qualified wiring harness; if it meets the requirements, the normal wiring harness is marked as a substandard wiring harness;

[0015] Step 3: Retest the substandard wiring harnesses identified by the calibrator. Test the substandard wiring harnesses within a set voltage range and determine whether they are abnormal based on the current values associated with the substandard wiring harnesses. The specific sub-steps are as follows:

[0016] S31. Testing the substandard wiring harness based on a preset voltage value interval: gradually increasing the operating voltage of the substandard wiring harness from a minimum value to a maximum value within the voltage value interval to confirm a voltage climbing curve, and recording a current value curve generated during the climbing phase, wherein the voltage value interval is the preset interval;

[0017] S32. Based on the preset resistance parameter C and the confirmed voltage ramp curve, a standard current variation curve associated with the voltage ramp curve is generated, where the current value = the voltage value ÷ the resistance parameter C. Based on the different voltages associated with different moments in the voltage ramp curve, different currents associated with different moments can be determined, and the corresponding associated standard current variation curves are then generated.

[0018] S33, placing the standard current change curve and the current value curve in the same two-dimensional coordinate system, and moving the standard current change curve by ±X1 to identify a set of moving regions, where X1 is a preset current fluctuation value, identifying a portion of the current value curve that is located in the moving region, and calibrating the identified portion of the curve as the standard curve;

[0019] Record the total line length ratio ZB of the standard curve located in the current value curve, where ZB = standard curve line length ÷ current value curve line length. If ZB is less than 80%, the substandard wiring harness will be calibrated as an abnormal wiring harness, and an abnormal signal will be generated for display. If ZB is greater than or equal to 80%, no calibration will be performed, indicating that the substandard wiring harness will not affect normal use in the future.

[0020] Preferably, the multi-harness test system comprises:

[0021] At the initial wiring harness evaluation end, a preset pulse signal is used to synchronously test multiple wiring harnesses to identify whether there is a reflected signal at the signal transmitter. Based on the identification results, the faulty wiring harness and the normal wiring harness are identified. Then, based on the waveform difference between the pulse signal and the reflected signal in the abnormal wiring harness, the cause of the abnormality of the faulty wiring harness is identified and displayed;

[0022] The qualified wiring harness assessment end, based on the normal wiring harness determined in the multi-wiring harness, confirms the received signal associated with the normal wiring harness during the synchronous test from the signal receiving end, confirms the attenuation rate of the corresponding pulse signal in the corresponding normal wiring harness based on the waveform characteristics associated with the received signal, and assesses whether the normal wiring harness is a qualified wiring harness based on the attenuation rate;

[0023] At the abnormal wiring harness assessment end, the substandard wiring harnesses that have been calibrated are retested, and the substandard wiring harnesses are tested through the set voltage value range. Based on the current value performance associated with the substandard wiring harness, it is assessed whether the substandard wiring harness is an abnormal wiring harness.

[0024] The present invention provides a multi-harness testing method and system. Compared with the prior art, it has the following advantages:

[0025] When the present invention performs synchronous testing on multiple wiring harnesses, the reflection signal is confirmed based on the reflection condition of the corresponding wiring harness, and the polarity of the reflection signal is analyzed to confirm whether the polarity between the reflection signal and the pulse signal is the same. If the confirmation result is the same, it means that there is an impedance abnormality point in the corresponding wiring harness. If the confirmation result is opposite, it means that there is a low resistance in the corresponding wiring harness. The step-by-step test confirmation method can effectively confirm whether the corresponding wiring harness is a normal wiring harness, improve the comprehensiveness of the test process, and quickly locate the faulty wiring harness.

[0026] For the confirmed normal wiring harness, the compliance test is carried out again. Based on the signal characteristics of the corresponding wiring harness transmission signal, the attenuation rate associated with the corresponding wiring harness is confirmed. Based on the numerical parameters of the attenuation rate, it is locked whether the corresponding normal wiring harness is a qualified wiring harness or a substandard wiring harness. For the substandard wiring harness, the voltage range is used and the internal voltage value of the wiring harness is gradually increased to confirm the current numerical performance associated with the corresponding wiring harness. Based on the specific numerical performance results, it is confirmed whether the corresponding substandard wiring harness will affect normal use in the future, improve the overall assessment effect between the wiring harnesses, ensure the comprehensiveness of the comprehensive test, and enable multiple wiring harnesses to obtain effective test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of the process of the present invention;

[0028] Figure 2 It is a schematic diagram of the principle framework of the present invention. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] First embodiment

[0031] See also Figure 1 , this application provides a multi-harness testing method, comprising the following steps:

[0032] Step 1: Use a preset pulse signal to synchronously test multiple wiring harnesses to identify whether there is a reflected signal at the signal transmitting end. Based on the identification result, lock the faulty wiring harness and the normal wiring harness. Then, based on the waveform difference between the pulse signal and the reflected signal in the abnormal wiring harness, lock the abnormal cause of the faulty wiring harness and display it. Specifically, when performing pulse testing on the wiring harness, give priority to determining a group of pulse signals that are most suitable for testing. The amplitude, width and frequency of the pulse signal are all set values, which are prepared in advance by relevant personnel. Each different wiring harness is tested with a corresponding pulse signal. If there is a node abnormality in the corresponding wiring harness, a reflected signal will be generated at the abnormal node. Based on the specific form of the corresponding reflected signal, the corresponding abnormal cause can be locked, which is convenient for subsequent relevant personnel to perform maintenance and repairs.

[0033] The specific method of locking the faulty wiring harness and the abnormality cause is as follows:

[0034] S11. A preset pulse signal is transmitted from a signal transmitting end to each wiring harness in the multi-wiring harness to identify whether the corresponding wiring harness generates a reflection signal. If a reflection signal is generated, the corresponding wiring harness is marked as a faulty wiring harness. If no reflection signal is generated, the corresponding wiring harness is marked as a normal wiring harness (i.e., the corresponding pulse signal is transmitted normally from the transmitting end to the receiving end without any reflection). The signal transmitting end can directly receive the reflection signal and, based on the received result, assess whether a reflection signal exists in the corresponding wiring harness.

[0035] S12. Confirm the signal waveforms of the pulse signal and the reflected signal. Use the starting point of the pulse signal waveform as the calibration point, use the amplitude associated with the calibration point as the reference amplitude, and calibrate it as Jz. Then confirm the specific amplitude associated with the turning point of the internal signal waveform of the reflected signal, and calibrate it as Fz. The waveform segments before and after the turning point have opposite trends. That is, when the waveform at one end rises, after passing the waveform turning point, the subsequent waveform falls. Similarly, when the waveform at one end falls, after passing the waveform turning point, the subsequent waveform rises. Use: Fz-Jz=Tz to confirm the waveform feature Tz associated with the reflected signal.

[0036] If Tz is less than 0, it means that the reflected signal and the pulse signal are in the opposite state, that is, the amplitude line associated with the calibration point is used as the baseline, the pulse signal is above the baseline, and the reflected signal is below the baseline, then it is in the opposite signal state, and a low-resistance signal is directly generated. The low resistance is most likely caused by a short circuit inside the harness. When there is low resistance inside the harness, a set of waveforms with opposite polarity will be reflected back due to the presence of the pulse signal, that is, the reflected signal is in the opposite state to the pulse signal. Then confirm the time t from the start of the pulse signal transmission to the receipt of the reflected signal, and use: L1=v×t / 2 to confirm the distance parameter L1 of the abnormal node, where v is a preset value, representing the transmission speed of the signal in the harness, which is prepared in advance by relevant personnel, and the generated low-resistance signal and distance parameter L1 are displayed;

[0037] If Tz>0, it means that the reflected signal exists, but it does not present an opposite state to the pulse signal. In this case, an impedance mismatch point presence signal is directly generated. Based on the time t from the start of pulse signal transmission to the reception of the reflected signal, the distance parameter L2 of the abnormal node is determined using the formula: L2=v×t / 2. The generated impedance mismatch point presence signal and distance parameter L2 are displayed.

[0038] Its Tz cannot be equal to 0. If it is equal to 0, it means there is no reflected signal. Then this type of wiring harness is a normal wiring harness, so Tz here cannot be equal to 0.

[0039] Specifically, during normal testing, the signal transmitted in the wiring harness will be transmitted from the transmitting end to the receiving end. However, when there is an abnormal node inside the wiring harness, a reflected signal will be generated. The waveform polarity of the reflected signal generated by different types of abnormal nodes is different, either the same as the polarity of the pulse signal or the opposite to the polarity of the pulse signal. Therefore, based on the specific performance state of the signal waveform corresponding to the reflected signal and the associated time parameters, the location of the abnormal node associated with the corresponding reflected signal can be locked, and the abnormal cause associated with the abnormal node can be locked simultaneously. By determining the amplitude standard and the method of determining the amplitude, the corresponding abnormal cause can be quickly locked.

[0040] Step 2: Based on the normal wiring harness determined in the multi-wiring harness, confirm the received signal associated with the normal wiring harness during the synchronization test from the signal receiving end, confirm the attenuation rate of the corresponding pulse signal in the corresponding normal wiring harness based on the waveform characteristics associated with the received signal, and evaluate whether the normal wiring harness is a qualified wiring harness based on the attenuation rate. Specifically, the better the overall performance of the corresponding wiring harness, the weaker its signal strength attenuation capability. Based on the specific strength data of the wiring harness, the attenuation rate generated by the corresponding pulse signal during the transmission process can be confirmed to perform relevant evaluations of qualified wiring harnesses and non-qualified wiring harnesses. The specific sub-steps for evaluating whether a normal wiring harness is a qualified wiring harness are as follows:

[0041] S21. Confirm the signal characteristics of the preset pulse signal, lock the amplitude and width associated with the pulse signal, calibrate the confirmed amplitude as Fz, calibrate the horizontal width between the start point and the end point of the pulse signal waveform as Kd, and use: XT = Fz × C1 + Kd × C2 to confirm the signal characteristic XT associated with this pulse signal, where C1 and C2 are preset fixed coefficient factors, and their specific values are determined by the operator based on experience;

[0042] S22: Using the same processing method as step S21, confirm the signal characteristics of the received signal associated with the normal line bundle, and mark the different signal characteristics confirmed by different normal line bundles as T k , where k represents different normal harnesses, using: XJ k =[(XT-T k )÷XT]×100% Confirm the attenuation rate XJ associated with the corresponding normal harness k , evaluate the attenuation rate XJ associated with the normal harness k Is it satisfied: XJ k ≥20%. If it meets the requirement, the normal wiring harness will be marked as a substandard wiring harness. Otherwise, the normal wiring harness will be marked as a standard wiring harness.

[0043] Specifically, when confirming whether the corresponding wiring harness meets the standards or not, it is necessary to evaluate the performance of the corresponding wiring harness in actual use based on the specific waveform attenuation during the corresponding signal transmission process. However, in actual processing, the signal attenuation rate generated by a normal wiring harness is generally not too high. If the signal attenuation rate is too large, it will cause the normal use behavior of such wiring harness in the later stage, resulting in the deterioration of the use effect of such wiring harness, and the use effect of the wiring harness cannot be fully guaranteed;

[0044] For the substandard wiring harnesses identified, it is necessary to re-analyze the normal use status of such substandard wiring harnesses during later use. Based on the specific performance of the voltage and current values, the performance of such substandard wiring harnesses in actual use is evaluated to conduct a comprehensive assessment and complete the comprehensive assessment and analysis of multiple groups of wiring harnesses.

[0045] Step 3: Retest the substandard wiring harnesses identified by the calibrator. Test the substandard wiring harnesses within a set voltage range and determine whether they are abnormal based on the current values associated with the substandard wiring harnesses. The specific sub-steps for this assessment are as follows:

[0046] S31. Testing the substandard wiring harness based on a preset voltage value range: gradually increasing the operating voltage of the substandard wiring harness from a minimum value to a maximum value within the voltage value range to confirm a voltage rise curve, and recording a current value curve generated during the rise phase. The voltage value range is a preset range, which is set in advance by the operator based on experience.

[0047] S32. Based on the preset resistance parameter C and the confirmed voltage ramp curve, a standard current variation curve associated with the voltage ramp curve is generated, where the current value = the voltage value ÷ the resistance parameter C. Based on the different voltages associated with different moments in the voltage ramp curve, different currents associated with different moments can be determined, and the corresponding associated standard current variation curves are then generated.

[0048] S33, placing the standard current change curve and the current value curve in the same two-dimensional coordinate system, and moving the standard current change curve by ±X1 to determine a set of moving regions, where X1 is a preset current fluctuation value, which is prepared in advance by relevant operators based on experience, and identifying a portion of the current value curve that is located in the moving region, and calibrating the identified portion of the curve as the standard curve;

[0049] Record the total length ratio ZB of the standard curve located on the current value curve, where ZB = standard curve line length ÷ current value curve line length. If ZB ≥ 80%, no calibration is performed, indicating that this substandard wiring harness will not affect subsequent normal use. If ZB < 80%, the substandard wiring harness is calibrated as an abnormal wiring harness, and an abnormal signal is generated synchronously for display for external personnel to view.

[0050] Specifically, during the normal testing of the wiring harness, the relevant current value curve is confirmed based on the corresponding voltage parameter change process, and then the standard current curve is determined based on the set specific standards. The confirmed current value curve is compared with the standard current curve, and the corresponding current fluctuation area is confirmed by the standard current curve. Then, the specific curve characteristics associated with the corresponding current value curve and the fluctuation area are evaluated, and the corresponding wiring harness usage status is evaluated. It is locked whether the corresponding wiring harness will affect normal use, so as to achieve better multi-wiring harness assessment and analysis management effects.

[0051] Second embodiment

[0052] Multi-harness test system, including:

[0053] At the initial wiring harness evaluation end, a preset pulse signal is used to synchronously test multiple wiring harnesses to identify whether there is a reflected signal at the signal transmitter. Based on the identification results, the faulty wiring harness and the normal wiring harness are identified. Then, based on the waveform difference between the pulse signal and the reflected signal in the abnormal wiring harness, the cause of the abnormality of the faulty wiring harness is identified and displayed;

[0054] The qualified wiring harness assessment end, based on the normal wiring harness determined in the multi-wiring harness, confirms the received signal associated with the normal wiring harness during the synchronous test from the signal receiving end, confirms the attenuation rate of the corresponding pulse signal in the corresponding normal wiring harness based on the waveform characteristics associated with the received signal, and assesses whether the normal wiring harness is a qualified wiring harness based on the attenuation rate;

[0055] At the abnormal wiring harness assessment end, the substandard wiring harnesses that have been calibrated are retested, and the substandard wiring harnesses are tested through the set voltage value range. Based on the current value performance associated with the substandard wiring harness, it is assessed whether the substandard wiring harness is an abnormal wiring harness.

[0056] Some of the data in the above formulas are dimensionless and numerically calculated. Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0057] The above embodiments are only used to illustrate the technical method of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. A multi-harness testing method, characterized in that: The following steps are involved: Step 1: Use a preset pulse signal to synchronously test multiple wiring harnesses to identify whether there is a reflected signal at the signal transmitting end. Based on the identification result, the faulty wiring harness and the normal wiring harness are identified. Then, based on the waveform difference between the pulse signal and the reflected signal in the faulty wiring harness, the cause of the abnormality of the faulty wiring harness is identified and displayed; Step 2: Based on the normal wiring harness determined within the multiple wiring harnesses, confirm the received signal associated with the normal wiring harness during the synchronization test from the signal receiving end, confirm the attenuation rate of the corresponding pulse signal within the corresponding normal wiring harness based on the waveform characteristics associated with the received signal, and assess whether the normal wiring harness is a qualified wiring harness based on the attenuation rate; Step 3: Retest the substandard wiring harnesses identified by the calibrator. Test the substandard wiring harnesses within a set voltage range and determine whether the substandard wiring harnesses are abnormal based on the current values associated with the substandard wiring harnesses. In step 3, the specific sub-steps for evaluating whether the substandard wiring harness is an abnormal wiring harness are as follows: S31. Testing the substandard wiring harness based on a preset voltage value interval: gradually increasing the operating voltage of the substandard wiring harness from a minimum value to a maximum value within the voltage value interval to confirm a voltage climbing curve, and recording a current value curve generated during the climbing phase, wherein the voltage value interval is the preset interval; S32. Based on the preset resistance parameter C and the confirmed voltage ramp curve, a standard current variation curve associated with the voltage ramp curve is generated, where the current value = the voltage value ÷ the resistance parameter C. Based on the different voltages associated with different moments in the voltage ramp curve, different currents associated with different moments can be determined, and the corresponding associated standard current variation curves are then generated. S33, placing the standard current change curve and the current value curve in the same two-dimensional coordinate system, and moving the standard current change curve by ±X1 to identify a set of moving regions, where X1 is a preset current fluctuation value, identifying a portion of the current value curve that is located in the moving region, and calibrating the identified portion of the curve as the standard curve; Record the total line length ratio ZB of the standard curve located in the current value curve, where ZB = standard curve line length ÷ current value curve line length. If ZB is less than 80%, the substandard wiring harness will be calibrated as an abnormal wiring harness, and an abnormal signal will be generated synchronously for display.

2. The multi-harness testing method according to claim 1, wherein: In step 1, the specific method of locking the faulty wiring harness is: S11. A preset pulse signal is transmitted from a signal transmitting end to each wiring harness in the multi-wiring harness to identify whether the corresponding wiring harness generates a reflection signal. If a reflection signal is generated, the corresponding wiring harness is marked as a faulty wiring harness; if no reflection signal is generated, the corresponding wiring harness is marked as a normal wiring harness. S12. Confirm the signal waveforms of the pulse signal and the reflected signal. Use the starting point of the pulse signal waveform as a calibration point, use the amplitude associated with the calibration point as a reference amplitude, and calibrate it as Jz. Then confirm the specific amplitude associated with the turning point of the internal signal waveform of the reflected signal, and calibrate it as Fz. The waveform segments before and after the turning point have opposite trends. Use: Fz-Jz=Tz to confirm the waveform feature Tz associated with the reflected signal. If Tz is less than 0, it means that the reflected signal and the pulse signal are in opposite states. In this case, a low-resistance signal is directly generated. The time t from the start of pulse signal transmission to the reception of the reflected signal is then confirmed. The distance parameter L1 of the abnormal node is confirmed using the formula: L1=v×t / 2. v is a preset value, representing the transmission speed of the signal in the wiring harness. The generated low-resistance signal and distance parameter L1 are displayed.

3. The multi-harness testing method according to claim 2, wherein: In step S12, if Tz>0, it means that a reflected signal exists, but it does not present an opposite state to the pulse signal. In this case, an impedance mismatch point existence signal is directly generated, and the distance parameter L2 of the abnormal node is confirmed using: L2=v×t / 2 based on the time t from the start of pulse signal transmission to the reception of the reflected signal. The generated impedance mismatch point existence signal and distance parameter L2 are displayed.

4. The multi-harness testing method according to claim 1, wherein: In step 2, the specific method of evaluating whether a normal wiring harness is a qualified wiring harness based on the attenuation rate is as follows: S21. Confirm the signal characteristics of the preset pulse signal, lock the amplitude and width associated with the pulse signal, calibrate the confirmed amplitude as Fz, calibrate the horizontal width between the start point and the end point of the pulse signal waveform as Kd, and use: XT = Fz × C1 + Kd × C2 to confirm the signal characteristic XT associated with this pulse signal, where C1 and C2 are preset fixed coefficient factors; S22: Using the same processing method as step S21, confirm the signal characteristics of the received signal associated with the normal line bundle, and mark the different signal characteristics confirmed by different normal line bundles as T k , where k represents different normal harnesses, using: XJ k =[(XT-T k )÷XT]×100% Confirm the attenuation rate XJ associated with the corresponding normal harness k , evaluate the attenuation rate XJ associated with the normal harness k Is it satisfied: XJ k ≥20%. If not met, the normal wiring harness will be calibrated as a qualified wiring harness.

5. The multi-harness testing method according to claim 4, characterized in that: In step S22, if XJ k Meet XJ k If the value is ≥20%, the normal wiring harness will be marked as a substandard wiring harness.

6. The multi-harness testing method according to claim 1, wherein: In step S33 , if ZB≥80%, no calibration is performed, which means that the substandard wiring harness will not affect normal use in the future.

7. A multi-beam test system, the test system being operated according to the multi-beam test method according to any one of claims 1 to 6, characterized in that: include: At the initial wiring harness evaluation end, a preset pulse signal is used to synchronously test multiple wiring harnesses to identify whether there is a reflected signal at the signal transmitter. Based on the identification results, the faulty wiring harness and the normal wiring harness are identified. Then, based on the waveform difference between the pulse signal and the reflected signal in the faulty wiring harness, the cause of the abnormality of the faulty wiring harness is identified and displayed; The qualified wiring harness assessment end, based on the normal wiring harness determined in the multi-wiring harness, confirms the received signal associated with the normal wiring harness during the synchronous test from the signal receiving end, confirms the attenuation rate of the corresponding pulse signal in the corresponding normal wiring harness based on the waveform characteristics associated with the received signal, and assesses whether the normal wiring harness is a qualified wiring harness based on the attenuation rate; At the abnormal wiring harness assessment end, the substandard wiring harnesses that have been calibrated are retested, and the substandard wiring harnesses are tested through the set voltage value range. Based on the current value performance associated with the substandard wiring harness, it is assessed whether the substandard wiring harness is an abnormal wiring harness.

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