Fault indicator automated testing fixture and method of use
By using a low-power current pulse controlled by a PLC and an automatic verification module for detection, the problems of low efficiency and high safety risks in fault indicator testing are solved, achieving efficient and reliable automated testing, which is suitable for fault indicator testing in power systems.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- STATE GRID HEBEI ELECTRIC POWER RES INST
- Filing Date
- 2026-06-05
- Publication Date
- 2026-07-24
AI Technical Summary
Existing fault indicator testing suffers from low efficiency, poor consistency, and high safety risks. In particular, contactors in automated solutions are prone to burn-out failure due to electric arc impact, resulting in low reliability.
The test formula is loaded using a programmable logic controller (PLC), combined with a programmable pulse power supply and a pulse excitation assembly. The fault indicator is triggered by generating an equivalent instantaneous magnetic field through a low-power current pulse, and the action area is detected by an automatic verification module to avoid the switching of real high current.
It significantly extends the service life of testing fixtures, reduces maintenance costs and safety hazards, improves testing efficiency and consistency, and meets the needs of long-term industrial production.
Smart Images
Figure CN122449451A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of fault indicator factory testing technology, and in particular to an automated testing fixture for fault indicators and its usage method. Background Technology
[0002] Fault indicators are core devices in power systems used to monitor line short circuits and overcurrent faults. Before leaving the factory, their action response performance must be verified by simulating instantaneous high current conditions to ensure reliable line fault detection and location. They are important supporting equipment for the safe operation of power distribution networks.
[0003] Currently, fault indicator testing mainly relies on manual operation and traditional automated solutions. Manual testing requires manually clamping the product, starting a high-current generator, and judging the results by visually observing the flip-up tags and indicator light status, and then manually recording the results. Traditional automated solutions use high-power contactors or relays to automatically switch high currents on and off, replacing manual operation of excitation and switching.
[0004] Manual testing suffers from problems such as low efficiency, poor consistency, high safety risks, and lack of data traceability. In traditional automation solutions, contactors are frequently subjected to instantaneous high current surges, which can easily lead to arc erosion, adhesion failure, short switch life, low tooling reliability, and high maintenance costs, making it difficult to meet the needs of industrial mass production. Summary of the Invention
[0005] This invention provides an automated testing fixture and method for fault indicators to solve the problems of low efficiency, poor consistency, high safety risks, and especially the low reliability of contactors in automated solutions due to arc impact.
[0006] In a first aspect, embodiments of the present invention provide an automated testing fixture for a fault indicator, comprising: A test recipe matching the fault indicator under test (FAT) is loaded into a programmable logic controller (PLC). The test recipe includes excitation parameters and verification parameters. A programmable pulse power supply is electrically connected to the PLC, and the input terminal of the pulse excitation assembly is electrically connected to the output terminal of the programmable pulse power supply. The FAT is placed in an adapter nest to position the internal sensor of the FAT within the effective excitation area of the pulse excitation assembly. Based on the excitation parameters, the PLC controls the programmable pulse power supply to output current pulses to the pulse excitation assembly, generating an instantaneous magnetic field equivalent to a preset instantaneous current, triggering the FAT to operate. An automatic verification module is electrically connected to the PLC and is used to detect the operating area of the FAT according to the verification parameters sent by the PLC, based on the control signals sent by the PLC, to obtain the test results.
[0007] In one possible implementation, the adapter nest is provided with a positioning nest, in which the fault indicator under test is placed and the internal sensor of the fault indicator under test is positioned within the effective excitation area of the pulse excitation assembly.
[0008] In one possible implementation, the fault indicator under test is a cable-type indicator, the pulse excitation assembly is a primary conductor rod, and the positioning nest is provided with a through hole or U-shaped groove, which is coaxially corresponding to the primary conductor rod. When the cable-type indicator is placed in the positioning nest, the primary conductor rod passes through the annular current transformer (CT) sensing port of the cable-type indicator.
[0009] In one possible implementation, the fault indicator under test is an overhead linear indicator, the pulse excitation assembly is a planar excitation coil, and the positioning nest is used to fix the sensing surface of the overhead linear indicator at a preset position directly above the planar excitation coil.
[0010] One possible implementation also includes: A safety shield is installed over the pulse excitation assembly and the adapter nest; A safety door lock is installed on the safety protective cover and is electrically interlocked with the PLC.
[0011] In one possible implementation, the automatic verification module is an industrial camera.
[0012] Secondly, embodiments of the present invention provide a method for using an automated testing fixture for fault indicators, employing the automated testing fixture for fault indicators described in any of the above aspects or any possible implementations. The method includes: When the corresponding adapter nest is installed according to the model of the fault indicator under test, and the corresponding test recipe is loaded into the PLC, and the fault indicator under test is placed in the adapter nest, the PLC controls the programmable pulse power supply to output current pulses to the pulse excitation assembly according to the excitation parameters, generating an instantaneous magnetic field equivalent to a preset instantaneous current, triggering the fault indicator under test to act; the test recipe includes excitation parameters and verification parameters; The PLC sends the verification parameters and control signals to the automatic verification module; The automatic verification module, based on the control signal, detects the operating area of the fault indicator under test according to the verification parameters, determines the test result, and sends the test result to the PLC.
[0013] In one possible implementation, the verification parameters define the region of interest (ROI) of the industrial camera, and the ROI corresponds to the action display area of the fault indicator under test. The automatic verification module, based on the control signal and according to the verification parameters, detects the operating area of the fault indicator under test and determines the test result, including: Based on the control signal, it is detected whether the color or brightness of the ROI has changed. If the color or brightness has changed, it is determined that the fault indicator under test has performed an action.
[0014] In one possible implementation, the excitation parameter is a pre-calibrated parameter equivalent to the preset instantaneous current, and is stored in the test formula in the PLC.
[0015] In one possible implementation, Before the PLC controls the programmable pulse power supply to output current pulses to the pulse excitation assembly according to the excitation parameters, generating an instantaneous magnetic field equivalent to a preset instantaneous current, and triggering the operation of the fault indicator under test, the following steps are also included: The action response threshold of the reference fault indicator is confirmed using a standard high current. The fault indicator automated testing fixture is used, and the programmable pulse power supply is controlled by the PLC to gradually adjust the current pulse applied to the pulse excitation assembly until the reference fault indicator reaches the response threshold. The current pulse corresponding to the reference fault indicator reaching the response threshold is determined as the excitation parameter.
[0016] This invention provides an automated testing fixture and method for fault indicators. A test formula matching the fault indicator under test is loaded into a PLC. The test formula includes excitation parameters and verification parameters. A programmable pulse power supply is electrically connected to the PLC, and the input terminal of the pulse excitation assembly is electrically connected to the output terminal of the programmable pulse power supply. The fault indicator under test is placed in an adapter nest to position its internal sensor within the effective excitation area of the pulse excitation assembly. Based on the excitation parameters, the PLC controls the programmable pulse power supply to output current pulses to the pulse excitation assembly, generating an instantaneous magnetic field equivalent to a preset instantaneous current, triggering the fault indicator under test to activate. An automatic verification module is electrically connected to the PLC and, based on the control signals sent by the PLC and the verification parameters sent by the PLC, detects the activation area of the fault indicator under test to obtain the test results. In this embodiment of the invention, a PLC-controlled programmable pulse power supply outputs low-power current pulses, which utilizes an instantaneous magnetic field to simulate the effect of a preset large current. This eliminates the need for actual switching of hundreds to thousands of amperes of large current, thus fundamentally preventing problems such as arc erosion, contact adhesion, and contactor failure. It significantly extends the service life of the testing fixture, reduces maintenance costs and safety hazards, and improves testing efficiency, meeting the needs of long-term continuous industrial production. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0018] Figure 1 This is a schematic diagram of the automated testing fixture for fault indicators provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of an automated testing fixture for a fault indicator provided in another embodiment of the present invention; Figure 3 This is a schematic diagram of the location of the nest provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the safety shield and safety door lock provided in an embodiment of the present invention; Figure 5 This is a flowchart illustrating the method of using the automated testing fixture for fault indicators provided in this embodiment of the invention. Figure 6 This is a flowchart illustrating the method of using an automated testing fixture for a fault indicator, provided in another embodiment of the present invention. Detailed Implementation
[0019] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
[0020] See Figure 1 The diagram illustrates an automated testing fixture for a fault indicator provided by an embodiment of the present invention, which is described in detail below: The automated testing fixture for fault indicators may include: PLC10, fault indicator under test 20, programmable pulse power supply 30, pulse excitation assembly 40, adapter nest 50, and automatic verification module 60. The PLC10 loads a test recipe that matches the fault indicator 20 under test. The test recipe includes excitation parameters and verification parameters. The programmable pulse power supply 30 is electrically connected to the PLC 10, and the input terminal of the pulse excitation assembly 40 is electrically connected to the output terminal of the programmable pulse power supply 30. The fault indicator 20 under test is placed in the adapter nest 50 to position the internal sensor of the fault indicator 20 under test within the effective excitation area of the pulse excitation assembly 40. According to the excitation parameters, the PLC 10 controls the programmable pulse power supply 30 to output current pulses to the pulse excitation assembly 40, generating an instantaneous magnetic field equivalent to a preset instantaneous current, which triggers the fault indicator 20 under test to operate. The automatic verification module 60 is electrically connected to the PLC10 and is used to detect the operating area of the fault indicator 20 under test according to the control signals sent by the PLC10 and the verification parameters sent by the PLC10, so as to obtain the test results.
[0021] Optionally, the PLC10 is the control core of the entire automated fault indicator testing fixture, used to uniformly schedule the entire testing process. It stores test recipes corresponding to different models of fault indicators. The test recipes include excitation parameters and verification parameters. Understandably, depending on the model of the indicator under test, such as model A, the operator will install the corresponding model A adapter and load the model A test recipe into the PLC10. The recipe pre-stores calibrated excitation parameters, such as the excitation parameters and verification parameters required for an equivalent 800A fault current.
[0022] The excitation parameters are a set of parameters for a group of current pulses. These current pulses, with power lower than a preset power, are collectively referred to as low-power current pulses. They are used to output to the pulse excitation assembly via a programmable pulse power supply, causing the pulse excitation assembly to generate an instantaneous magnetic field equivalent to a preset instantaneous current, triggering the fault indicator under test (FAT). The preset instantaneous current is a large instantaneous current greater than a preset current that can trigger the FAT. The excitation parameters may include the pulse current amplitude and pulse duration. Physically, the instantaneous magnetic field generated by this pulse at the sensor inside the FAT is equivalent to the magnetic field generated by a preset standard large current, such as 800A, thus reliably triggering the FAT.
[0023] In one embodiment, the excitation parameters are pre-calibrated parameters equivalent to a preset instantaneous current and are stored in the test formula in PLC10.
[0024] The calibration procedure for the excitation parameters is as follows: The action response threshold of the reference fault indicator is confirmed using a standard high current. On this automated test fixture for fault indicators, the current pulses applied to the pulse excitation assembly are gradually adjusted using a PLC10 and a programmable pulse power supply until the reference fault indicator reaches the response threshold.
[0025] Optionally, the excitation parameters are not obtained through theoretical calculations, but are determined through a pre-calibrated experimental process. When calibrating the excitation parameters, firstly, a standard high-current testing device is used to test the reference fault indicator, gradually adjusting the output current to accurately confirm the true action response threshold of the reference fault indicator; The reference fault indicator is installed in this automated fault indicator testing system. The programmable pulse power supply 30 is controlled by the automatic verification module PLC10 to gradually adjust the current pulse parameters output to the pulse excitation assembly 40. The working status of the reference fault indicator is continuously observed until the reference fault indicator reaches its action response threshold and reliably triggers the action. This process is a debugging process. The operator or calibration program will gradually adjust the low-power pulse parameters applied to the pulse excitation assembly 40, for example, adjusting the pulse current amplitude or pulse duration, for example, starting from 1A, 100ms and gradually adjusting to 5A, 100ms. During the gradual adjustment process, the baseline fault indicator is continuously observed. When adjusted to a specific set of low-power pulse parameters, such as 5A and 100ms, the baseline fault indicator reaches its previously calibrated response threshold, indicating that an action has occurred. At this point, an equivalent relationship is established. The PLC10 calibrates this set of low-power pulse parameters, 5A and 100ms, as equivalent to 800A excitation parameters and stores this set of excitation parameters in the test recipe for the corresponding fault indicator model. In subsequent batch automated testing of this fault indicator model, the PLC10 only needs to call this test recipe to accurately reproduce the equivalent excitation effect.
[0026] Optionally, the calculation logic and processing flow for obtaining the excitation parameters can be pre-calibrated: The input sources for this process are the standard high current value applied on the reference test bench and the real-time low-power pulse parameter setting value of the programmable pulse power supply 30 on this fixture. Logical steps: Step 1: On a separate test bench that can generate a standard high current, gradually increase the current and accurately record the standard action response threshold at which the reference fault indicator takes effect, for example, 800A. Step 2: Place the reference indicator in the modular adapter nest 50 of this fixture, and gradually adjust the low-power pulse parameters output by the programmable pulse power supply 30 through PLC10, such as current amplitude and duration. Step 3: Continuously adjust the low-power pulse parameters until the reference fault indicator just reaches the standard action response threshold confirmed in Step 1, i.e., an action occurs. Step four: Record the parameters of the low-power pulse applied at this time, that is, calibrate them as excitation parameters equivalent to the standard high current; Output results and flow: The final output of the process is a set of excitation parameters, such as 5A, 100ms. These excitation parameters are then stored in the corresponding test recipe of the PLC10 and applied to subsequent batch automated testing.
[0027] The excitation parameter is the sole instruction used by the PLC10 to control the programmable pulse power supply 30 to perform excitation actions. When the PLC10 performs an excitation action, it directly calls this excitation parameter to drive the pulse excitation assembly 40 to work.
[0028] In one embodiment, the automatic verification module 60 can be an industrial camera.
[0029] The verification parameters define the region of interest (ROI) of the industrial camera, and the ROI area precisely corresponds to the action display area of the fault indicator under test. The control signal instructs the industrial camera to detect the color or brightness of the ROI. If the color or brightness changes, it is determined that the fault indicator under test has performed an action.
[0030] Optionally, the automatic verification module 60 uses an industrial camera to automatically detect the operating status of the fault indicator under test.
[0031] Verification parameters are a set of criteria used by automated testing systems to detect the operational status of the fault indicator under test. Their physical meaning is the expected optical or electrical characteristics presented by the fault indicator after it operates, such as flipping a card or turning on a light, such as a specific color, brightness value, or signal level.
[0032] The verification parameters predefine the Region of Interest (ROI) for the industrial camera. These parameters include the coordinate definition of the ROI and the color change or brightness change thresholds used to determine Pass / Fail. These verification parameters are preset and fixed into the test formula during tooling debugging, based on the geometry and motion characteristics of the fault indicator under test. The ROI precisely corresponds to the motion display area of the fault indicator under test, such as the flip-card area or LED indicator area. The ROI is thus defined to cover only this motion area.
[0033] The decision-making role of the verification parameter is as follows: it is the core input for the PLC10 instruction automatic verification module 60 to perform the verification operation; the automatic verification module 60 compares its real-time test results with the expected value defined by the verification parameter to complete the automatic determination of Pass / Fail.
[0034] During testing, the PLC10 sends control signals to the industrial camera, instructing it to acquire image information of the ROI area and perform real-time detection of color or brightness changes within that ROI. The industrial camera only analyzes image information within the ROI. When a preset color change is detected in the ROI area, such as flipping from black to red, or a brightness change, such as an LED light turning from off to on, the fault indicator under test is determined to have successfully executed its action. If no corresponding change is detected, the fault indicator under test is determined to have not activated, thus completing the automatic determination of the test results. This method, based on precise mechanical positioning and fixed ROI detection, avoids complex AI visual recognition and achieves automated verification in a simple, reliable, and low-cost manner.
[0035] Optionally, the test recipe is a complete, fixed, and reusable set of automated test instructions for a specific model of fault indicator; it consists of excitation parameters, verification parameters, and specific mechanical alignment information; it serves as the overall logical scheduling basis for the automated test fixture of the fault indicator, ensuring that flexible automated testing with one-click start, automatic testing, and automatic judgment can be achieved for different models of products.
[0036] In one embodiment, such as Figure 2 or Figure 3 As shown, the adapter nest 50 is provided with a positioning nest 51, which is used to place the fault indicator under test 20 and position the internal sensor of the fault indicator under test 20 within the effective excitation area of the pulse excitation assembly 40.
[0037] The positioning nest 51 set on the adapter nest 50 is used to accurately place the fault indicator under test 20. The mechanical positioning structure stably limits the fault indicator under test 20, ensuring that the internal sensors of the fault indicator under test 20, such as CT or Hall element, can be reliably and accurately located in the effective excitation area of the pulse excitation assembly 40. This ensures that the relative position of the fault indicator under test 20 and the excitation source remains consistent during each test, so that the instantaneous magnetic field generated by the low-power current pulse can stably and equivalently trigger the fault indicator under test 20 to act, improving the consistency and repeatability of the test.
[0038] In this embodiment, the equivalent magnetic field excitation, precision mechanical positioning and automated optical verification are coordinated through the unified scheduling of PLC10. The test is completed without generating a real large current, avoiding the core technical bottleneck of high-power contactors failing due to arc erosion. This improves the reliability, safety and consistency of the test fixture, and enables flexible automated testing of multiple product models through formula management.
[0039] In one embodiment, the fault indicator 20 under test is a cable-type indicator, the pulse excitation assembly 40 is a primary conductor rod, and the positioning nest 51 is provided with a through hole or U-shaped groove, which is coaxially corresponding to the primary conductor rod. When the cable-type indicator is placed in the positioning nest, the primary conductor rod passes through the annular CT sensing port of the cable-type indicator.
[0040] Optionally, considering the structure and sensing characteristics of the cable-type fault indicator, the pulse excitation assembly 40 uses a primary side conductor rod to achieve magnetic field excitation. The primary side conductor rod is fixedly installed at the test station, and its two ends are electrically connected to the output terminals of the programmable pulse power supply 30 to pass in low-power current pulses to generate an equivalent instantaneous magnetic field.
[0041] The positioning cavity 51 on the adapter 50 is equipped with a through hole or U-shaped groove, the position and size of which match the position and outer diameter of the primary conductor rod. When the cable fault indicator is placed in the positioning cavity 51, the primary conductor rod can smoothly pass through the CT sensor port of the cable fault indicator, so that the primary conductor rod and the CT sensor port form a coaxial alignment relationship, truly replicating the installation and use state of the cable fault indicator on the actual power line.
[0042] With the above structural design, it can be ensured that when a low-power current pulse, such as 5A, is applied to the primary conductor rod, the instantaneous magnetic field generated around the primary conductor rod can be stably and accurately sensed by the internal sensor of the cable fault indicator, achieving equivalent excitation with a preset high-current magnetic field, such as the magnetic field generated when 800A flows through a real cable, ensuring that the cable fault indicator is reliably triggered and improving the consistency, accuracy and repeatability of the test.
[0043] Optionally, the primary conductor bar is typically made of a copper bar with high conductivity.
[0044] In one embodiment, the fault indicator 20 under test is an overhead linear indicator, the pulse excitation assembly 40 is a planar excitation coil, and the positioning nest 51 is used to fix the sensing surface of the overhead linear indicator at a preset position directly above the planar excitation coil.
[0045] Optionally, for overhead linear indicators, a bypass sensing principle is typically used, such as the specific testing method for Hall effect elements. In this application scenario, for the sensing method and installation structure of the overhead linear indicator, the pulse excitation assembly 40 uses a planar excitation coil to achieve equivalent magnetic field excitation. The planar excitation coil is fixedly installed inside the test fixture base 80, with the coil end face kept horizontal. For example, it is fixed by encapsulation with epoxy resin. Its lead-out end is electrically connected to the output end of the programmable pulse power supply 30 to generate a uniform and stable instantaneous magnetic field when a low-power current pulse is applied.
[0046] It should be noted that the test fixture in this embodiment is the automated test fixture for the fault indicator provided in this application. The test station base can be... Figure 2 The base 80 shown.
[0047] Corresponding to the structure of the pulse excitation assembly 40, the positioning nest 51 on the adapter nest 50 is designed to fix and clamp the overhead line indicator under test, ensuring its unique position. That is, the positioning nest has positioning and clamping functions, reliably fixing the overhead line indicator and preventing displacement or shaking during testing. The structure and position of the positioning nest 51 are precisely designed to ensure that when the overhead line indicator is placed in the positioning nest 51, its sensing surface is accurately positioned at a preset position directly above the planar excitation coil, maintaining a constant distance from the coil surface, so that the sensing surface is always within the effective magnetic field coverage of the planar excitation coil. For example, the constant distance can be set to 3 mm. The constancy of this distance is crucial for test repeatability. When a low-power pulse controlled by PLC10 is applied to the planar excitation coil, the spatial magnetic field generated at a specific distance of -3 mm directly above the planar excitation coil is equivalent to the magnetic field generated by a standard high current next to the overhead line, thus being accurately sensed by the sensing surface and triggering action.
[0048] Through the above positioning and structural settings, it can be ensured that the instantaneous magnetic field generated by the planar excitation coil when a low-power current pulse is applied can stably and equivalently act on the sensing surface of the overhead line type indicator, accurately simulating the magnetic field environment generated by a real large current next to the overhead line, thereby reliably triggering the action of the overhead line type indicator and ensuring the consistency, accuracy and repeatability of the test results.
[0049] In one embodiment, such as Figure 4 As shown, the automated test fixture for the fault indicator also includes: a safety guard 70 and a safety door lock 71.
[0050] A safety shield 70 is installed outside the pulse excitation assembly 40 and the adapter nest 50; Safety door lock 71 is installed on safety cover 70 and is electrically interlocked with PLC10.
[0051] Optionally, to ensure operator safety, a safety shield 70 is installed in the test area, including the adapter nest 50 and the pulse excitation assembly 40, to physically isolate the core test area from the external operating area, forming a closed test space. This prevents operators from directly contacting internal moving and electrical components during testing, improving operational safety. A safety lock 71 is installed on the safety shield 70, and the status signal of the safety lock 71 is electrically interlocked with the PLC 10. The safety lock 71 can be an electromagnetic lock or a safety switch.
[0052] Specifically, the PLC10 collects the locking status signal of the safety door lock 71 in real time. Only when the safety protective cover 70 is completely closed and the safety door lock 71 is in the locked state will the PLC10 allow the test process to be started, control the programmable pulse power supply 30 to output current pulses and execute the test. If the safety protective cover 70 is not closed or the safety door lock 71 is not locked, the PLC10 will prohibit the start of the test and maintain the locked state, thus eliminating the risk of false triggering from the control logic, fully protecting the personal safety of operators during product handling and tooling debugging, and meeting the safety requirements of industrial production.
[0053] Optionally, the safety guard 70 must be closed after the operator places the fault indicator and before the PLC10 applies the excitation pulse; at this time, the safety door lock 71 is locked. The signal status of safety door lock 71, such as locked or unlocked, is interlocked with the control logic of PLC 10. PLC 10 is programmed to check the signal from safety door lock 71 before applying an excitation pulse. Only when PLC 10 confirms that it has received a signal that safety door lock 71 is locked will it be allowed to continue applying the excitation pulse and subsequent steps. If safety door lock 71 is not locked, PLC 10 will pause the process and issue an alarm, prohibiting the application of pulses. After the test results are determined, the entire test cycle ends. At this time, PLC10 will perform an additional step: send a command to release the safety door lock 71. Only then can the operator safely open the safety cover 70, remove the tested fault indicator, and put in the next fault indicator to be tested.
[0054] This invention provides an automated testing fixture for fault indicators. A test formula matching the fault indicator under test is loaded into a PLC. The test formula includes excitation parameters and verification parameters. A programmable pulse power supply is electrically connected to the PLC, and the input terminal of the pulse excitation assembly is electrically connected to the output terminal of the programmable pulse power supply. The fault indicator under test is placed in an adapter nest to position the internal sensor of the fault indicator under test within the effective excitation area of the pulse excitation assembly. Based on the excitation parameters, the PLC controls the programmable pulse power supply to output current pulses to the pulse excitation assembly, generating an instantaneous magnetic field equivalent to a preset instantaneous current, triggering the fault indicator under test to activate. The automatic verification module is electrically connected to the PLC and is used to detect the operating area of the fault indicator under test according to the verification parameters sent by the PLC based on the control signals sent by the PLC, and obtain the test results. In this embodiment of the invention, the PLC controls the programmable pulse power supply to output low-power current pulses, and uses the instantaneous magnetic field equivalent to simulate the effect of a preset large current. It does not require actual switching of hundreds to thousands of amperes of large current, thus fundamentally eliminating problems such as arc erosion, contact adhesion, and contactor failure. This significantly extends the service life of the test fixture, reduces maintenance costs and safety hazards, and improves test efficiency, which can meet the needs of long-term continuous industrial production.
[0055] In this embodiment of the invention, by loading a test formula that matches the model of the fault indicator under test into the PLC, the test process of different products can be quickly switched without repeated manual adjustment of parameters. It can be compatible with the automated detection of multiple models of fault indicators, greatly improving the versatility of testing and switching efficiency, and meeting the needs of flexible industrial production.
[0056] In this embodiment of the invention, the excitation parameters and verification parameters are pre-fixed in the test formula and executed by precise control of PLC, avoiding errors caused by manual adjustment, ensuring that the excitation intensity and detection standards are completely consistent for each test, fundamentally solving the problems of large manual operation errors and inconsistent judgment standards in traditional testing, and improving the accuracy and repeatability of test results.
[0057] In this embodiment of the invention, the adapter nest can stably position the fault indicator under test and ensure that its internal sensors are precisely within the effective excitation area of the pulse excitation assembly, thus ensuring uniform, equivalent, and reliable magnetic field excitation, avoiding test failure or misjudgment due to positional deviation, and further improving test accuracy and stability.
[0058] In this embodiment of the invention, the automatic verification module, under the control of a PLC, automatically detects the action area of the fault indicator according to the verification parameters, replacing manual visual observation, avoiding fatigue, misjudgment, and omission, realizing automatic collection and automatic judgment of test results, improving test efficiency and objectivity, and facilitating data storage and quality traceability.
[0059] In this embodiment of the invention, the entire system is uniformly scheduled and automatically executed by a PLC. From excitation output to result judgment, no manual intervention is required throughout the entire process. This not only improves the testing speed but also avoids operators coming into contact with the testing area, reducing safety risks and achieving efficient, safe, and stable automated testing.
[0060] In this embodiment of the invention, both the pulse excitation assembly and the programmable pulse power supply use solid-state electronic devices, with a switching life of up to millions of cycles. This solves the problem of frequent contactor failures in existing automation solutions and ensures the high reliability required for industrial production.
[0061] In this embodiment of the invention, there is no high voltage or high current inside the test fixture. Furthermore, by setting up a safety guard and a safety lock, and interlocking the signal status of the safety lock with the PLC, it is ensured that the excitation process can only be executed when the guard is locked, thus eliminating safety hazards.
[0062] This invention provides a method for using an automated testing fixture for fault indicators, employing the automated testing fixture for fault indicators described in any of the above embodiments. (See also...) Figure 5 As shown, the usage method of the automated test fixture for fault indicators includes: Step 501: After installing the corresponding adapter nest according to the model of the fault indicator under test, loading the corresponding test recipe into the PLC, and placing the fault indicator under test in the adapter nest, the PLC controls the programmable pulse power supply to output current pulses to the pulse excitation assembly according to the excitation parameters, generating an instantaneous magnetic field equivalent to the preset instantaneous current, triggering the fault indicator under test to act; the test recipe includes excitation parameters and verification parameters.
[0063] In this step, first follow the attached... Figure 1 The automated testing fixture for fault indicators shown connects a PLC10, a programmable pulse power supply 30, a pulse excitation assembly 40, an automatic verification module 60, and an adapter nest 50. The PLC10 serves as the control core and is electrically connected to the programmable pulse power supply 30 and the automatic verification module 60. The output of the programmable pulse power supply 30 is electrically connected to the pulse excitation assembly 40. It is important to note that the adapter nest 50 must correspond to the model of the fault indicator under test. For example, if the model of the fault indicator under test is model A, then the adapter nest 50 is the adapter nest corresponding to the model A fault indicator under test. The test formula corresponding to the model A fault indicator under test is obtained and loaded into the PLC10. The test formula includes excitation parameters and verification parameters.
[0064] In one embodiment, the excitation parameters are pre-calibrated parameters equivalent to a preset instantaneous current and are stored in the test formula in the PLC.
[0065] The pre-calibration of the excitation parameters is performed before the PLC controls the programmable pulse power supply to output current pulses to the pulse excitation assembly according to the excitation parameters, generating an instantaneous magnetic field equivalent to the preset instantaneous current, which triggers the action of the fault indicator under test.
[0066] In one embodiment, such as Figure 6 As shown, the pre-calibration process for the excitation parameters is as follows: The action response threshold of the reference fault indicator is confirmed using a standard high current. An automated fault indicator testing fixture is used. A programmable pulse power supply is controlled by a PLC to gradually adjust the current pulse applied to the pulse excitation assembly until the reference fault indicator reaches the response threshold. The current pulse corresponding to the reference fault indicator reaching the response threshold is determined as the excitation parameter.
[0067] Optionally, the input source for the pre-calibrated excitation parameter processing flow is the standard high current value applied on the reference test bench and the real-time low-power pulse parameter setting value of the programmable pulse power supply 30 on this fixture. Logical steps: Step 1: On a separate test bench that can generate a standard high current, gradually increase the current and accurately record the standard action response threshold at which the reference fault indicator takes effect, for example, 800A. Step 2: Place the reference indicator in the modular adapter nest 50 of this fixture, and gradually adjust the low-power pulse parameters output by the programmable pulse power supply 30 through PLC10, such as current amplitude and duration. Step 3: Continuously adjust the low-power pulse parameters until the reference fault indicator just reaches the standard action response threshold confirmed in Step 1, i.e., an action occurs. Step four: Record the parameters of the low-power pulse applied at this time, that is, calibrate them as excitation parameters equivalent to the standard high current; Output results and flow: The final output of the process is a set of excitation parameters, such as 5A, 100ms. These excitation parameters are then stored in the corresponding test recipe of the PLC10 and applied to subsequent batch automated testing.
[0068] The excitation parameter is the sole instruction used by the PLC10 to control the programmable pulse power supply 30 to perform excitation actions. When the PLC10 performs an excitation action, it directly calls this excitation parameter to drive the pulse excitation assembly 40 to work.
[0069] In one embodiment, the verification parameters are a set of judgment indicators used by an automated testing system to detect the operational status of the fault indicator under test. Their physical meaning is the expected optical or electrical characteristics presented by the fault indicator under test after it operates, such as flipping a card or turning on a light, such as a specific color, brightness value or signal level.
[0070] The verification parameters predefine the region of interest (ROI) of the industrial camera. These parameters include the coordinate definition of the ROI and the color change threshold or brightness change threshold used to determine whether the camera passes or fails.
[0071] Optionally, after installing the fault indicator automated testing fixture, to ensure operator safety, a safety shield 70 is installed in the testing area, including the adapter nest 50 and pulse excitation assembly 40, to physically isolate the core testing area from the external operating area, forming a closed testing space. This prevents operators from directly contacting internal moving and electrical components during testing, improving operational safety. The safety shield 70 is equipped with a safety door lock 71, which is electrically interlocked with the PLC 10. See the appendix for details. Figure 4 The corresponding descriptions will not be repeated here.
[0072] In this step, PLC10 controls a low-power current pulse to be applied to the pulse excitation assembly 40 according to the excitation parameters, generating a spatial magnetic field. This magnetic field is equivalent to the magnetic field generated by a standard high current next to an overhead line, and is thus accurately sensed by the sensing surface in the fault indicator under test and triggered to take action.
[0073] Optionally, the verification parameters are preset and fixed in the test formula during tooling debugging, based on the geometric dimensions and motion characteristics of the fault indicator under test. The test formula is a complete, fixed, and reusable automated test instruction set for a specific model of fault indicator; it consists of excitation parameters, verification parameters, and specific mechanical alignment information; it serves as the overall logical scheduling basis for the automated test tooling of the fault indicator, ensuring that flexible automated testing with one-click start, automatic testing, and automatic judgment can be achieved for different models of products.
[0074] By coordinating the equivalent magnetic field excitation and precise mechanical positioning through the scheduling of PLC10, the fault indicator under test is triggered without generating a real large current. This avoids the core technical bottleneck of high-power contactors failing due to arc erosion, improves the reliability, safety and consistency of the test fixture, and enables flexible automated testing of multiple product models through formula management.
[0075] Step 502: The PLC sends verification parameters and control signals to the automatic verification module.
[0076] The automatic verification module can be used for industrial cameras.
[0077] The validation parameters define the ROI of the industrial camera, which precisely corresponds to the action display area of the fault indicator under test, such as the flip-card area or the LED indicator area. The ROI is defined to cover only this action area.
[0078] The decision-making role of the verification parameter is as follows: it is the core input for the PLC10 instruction automatic verification module 60 to perform the verification operation; the automatic verification module 60 compares its real-time test results with the expected value defined by the verification parameter to complete the automatic determination of Pass / Fail.
[0079] Step 503: The automatic verification module, based on the control signal, detects the action area of the fault indicator under test according to the verification parameters, determines the test result, and sends the test result to the PLC.
[0080] In one embodiment, the automatic verification module, based on control signals and verification parameters, detects the operating area of the fault indicator under test and determines the test result, including: Based on the control signal, it detects whether the color or brightness of the ROI changes. If the color or brightness changes, it is determined that the fault indicator under test has performed an action.
[0081] During testing, the PLC10 sends control signals to the industrial camera, instructing it to acquire image information of the ROI area and perform real-time detection of color or brightness changes within that ROI. The industrial camera only analyzes image information within the ROI. When a preset color change is detected in the ROI area, such as flipping from black to red, or a brightness change, such as an LED light turning from off to on, the fault indicator under test is determined to have successfully executed its action. If no corresponding change is detected, the fault indicator under test is determined to have not activated, thus completing the automatic determination of the test results. This method, based on precise mechanical positioning and fixed ROI detection, avoids complex AI visual recognition and achieves automated verification in a simple, reliable, and low-cost manner.
[0082] like Figure 6 As shown, after the test of the fault indicator is completed, the tested fault indicator is taken out, another fault indicator is installed in the corresponding adapter nest 50, the corresponding test recipe is loaded in the PLC, and the new fault indicator is placed in the adapter nest. Then, the process jumps to step 501 and continues until all the fault indicators under test have completed the factory test.
[0083] This invention provides a method for using an automated testing fixture for fault indicators. Using this automated testing fixture, when the corresponding adapter nest is installed according to the model of the fault indicator under test, and the corresponding test formula is loaded into the PLC, and the fault indicator under test is placed in the adapter nest, the PLC controls the programmable pulse power supply to output current pulses to the pulse excitation assembly according to the excitation parameters, generating an instantaneous magnetic field equivalent to a preset instantaneous current, triggering the fault indicator under test to operate. The test formula includes excitation parameters and verification parameters. The PLC sends verification parameters and control signals to the automatic verification module. Based on the control signals, the automatic verification module detects the operating area of the fault indicator under test according to the verification parameters, determines the test result, and sends the result back to the PLC. In this embodiment of the invention, the PLC controls the programmable pulse power supply to output low-power current pulses, utilizing an instantaneous magnetic field to simulate a preset high-current effect. This eliminates the need for actual switching of hundreds to thousands of amperes of current, fundamentally preventing problems such as arc erosion, contact adhesion, and contactor failure. It significantly extends the service life of the testing fixture, reduces maintenance costs and safety hazards, and improves testing efficiency, meeting the needs of long-term continuous industrial production.
[0084] In this embodiment of the invention, the excitation parameters and verification parameters are pre-fixed in the test formula and executed by precise control of PLC, avoiding errors caused by manual adjustment, ensuring that the excitation intensity and detection standards are completely consistent for each test, fundamentally solving the problems of large manual operation errors and inconsistent judgment standards in traditional testing, and improving the accuracy and repeatability of test results.
[0085] In this embodiment of the invention, the automatic verification module, under the control of a PLC, automatically detects the action area of the fault indicator according to the verification parameters, replacing manual visual observation, avoiding fatigue, misjudgment, and omission, realizing automatic collection and automatic judgment of test results, improving test efficiency and objectivity, and facilitating data storage and quality traceability.
[0086] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.
[0087] In the above embodiments, the descriptions of each embodiment have their own emphasis. Parts not detailed or described in a particular embodiment can be referred to in the relevant descriptions of other embodiments. Unless otherwise specified or in conflict with logic, the terminology and / or descriptions between different embodiments are consistent and can be referenced interchangeably. Technical features in different embodiments can be combined to form new embodiments based on their inherent logical relationships.
[0088] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.
Claims
1. An automated testing fixture for fault indicators, characterized in that, include: A test recipe matching the fault indicator under test is loaded into the programmable logic controller (PLC), and the test recipe includes excitation parameters and verification parameters. The programmable pulse power supply is electrically connected to the PLC, and the input terminal of the pulse excitation assembly is electrically connected to the output terminal of the programmable pulse power supply. The fault indicator under test is placed in the adapter nest to position the internal sensor of the fault indicator under test within the effective excitation area of the pulse excitation assembly. The PLC controls the programmable pulse power supply to output current pulses to the pulse excitation assembly based on the excitation parameters, generating an instantaneous magnetic field equivalent to a preset instantaneous current, triggering the operation of the fault indicator under test; the automatic verification module is electrically connected to the PLC and is used to detect the operation area of the fault indicator under test according to the control signal sent by the PLC and the verification parameters sent by the PLC, and obtain the test result.
2. The automated testing fixture for fault indicators according to claim 1, characterized in that, The adapter nest is provided with a positioning nest, which is used to place the fault indicator under test and position the internal sensor of the fault indicator under test within the effective excitation area of the pulse excitation assembly.
3. The automated testing fixture for fault indicators according to claim 2, characterized in that, The fault indicator under test is a cable-type indicator. The pulse excitation assembly is a primary conductor rod. The positioning nest is provided with a through hole or a U-shaped groove, which is coaxially corresponding to the primary conductor rod. When the cable-type indicator is placed in the positioning nest, the primary conductor rod passes through the annular current transformer (CT) sensing port of the cable-type indicator.
4. The automated testing fixture for fault indicators according to claim 2, characterized in that, The fault indicator under test is an overhead linear indicator, the pulse excitation assembly is a planar excitation coil, and the positioning nest is used to fix the sensing surface of the overhead linear indicator at a preset position directly above the planar excitation coil.
5. The automated test fixture for fault indicators according to any one of claims 1-4, characterized in that, Also includes: A safety shield is installed over the pulse excitation assembly and the adapter nest; A safety door lock is installed on the safety protective cover and is electrically interlocked with the PLC.
6. The automated test fixture for fault indicators according to any one of claims 1-4, characterized in that, The automatic verification module is an industrial camera.
7. A method for using an automated testing fixture for a fault indicator, characterized in that, The method using the automated test fixture for fault indicators according to any one of claims 1-6 comprises: When the corresponding adapter nest is installed according to the model of the fault indicator under test, and the corresponding test recipe is loaded into the PLC, and the fault indicator under test is placed in the adapter nest, the PLC controls the programmable pulse power supply to output current pulses to the pulse excitation assembly according to the excitation parameters, generating an instantaneous magnetic field equivalent to a preset instantaneous current, triggering the fault indicator under test to act; the test recipe includes excitation parameters and verification parameters; The PLC sends the verification parameters and control signals to the automatic verification module; The automatic verification module, based on the control signal, detects the operating area of the fault indicator under test according to the verification parameters, determines the test result, and sends the test result to the PLC.
8. The method of using the automated testing fixture for the fault indicator according to claim 7, characterized in that, The verification parameters define the region of interest (ROI) of the industrial camera, and the ROI corresponds to the action display area of the fault indicator under test. The automatic verification module, based on the control signal and according to the verification parameters, detects the operating area of the fault indicator under test and determines the test result, including: Based on the control signal, it is detected whether the color or brightness of the ROI has changed. If the color or brightness has changed, it is determined that the fault indicator under test has performed an action.
9. The method of using the automated testing fixture for the fault indicator according to claim 7, characterized in that, The excitation parameters are pre-calibrated parameters equivalent to the preset instantaneous current, and are stored in the test formula in the PLC.
10. The method of using the automated testing fixture for the fault indicator according to claim 9, characterized in that, Before the PLC controls the programmable pulse power supply to output current pulses to the pulse excitation assembly according to the excitation parameters, generating an instantaneous magnetic field equivalent to a preset instantaneous current, and triggering the operation of the fault indicator under test, the following steps are also included: The action response threshold of the reference fault indicator is confirmed using a standard high current. The fault indicator automated testing fixture is used, and the programmable pulse power supply is controlled by the PLC to gradually adjust the current pulse applied to the pulse excitation assembly until the reference fault indicator reaches the response threshold. The current pulse corresponding to the reference fault indicator reaching the response threshold is determined as the excitation parameter.