I. Introduction Electromagnetic relays are widely used in industrial control, agriculture, transportation, national defense, space technology, and daily life. They are indispensable basic components of electronic equipment for remote control, telemetry, communication, detection, and protection. Their proper functioning directly affects the stability and reliability of equipment or products containing them. With the development of relay technology and the continuous expansion of relay applications, the requirements for relay performance, lifespan, and reliability are becoming increasingly stringent. Throughout its lifespan, any product has stages such as storage, transportation, standby, and operation. Each stage corresponds to different environmental profiles and timeframes, requiring the product to complete its specified functions at every stage. For products that are in continuous operation, their operational reliability mainly depends on the environment and duration of the operation. For single-use products, since the storage time is much longer than the usage time, their operational reliability is related to the storage time. Therefore, using more scientific technical means to objectively predict and evaluate the operational and storage reliability of products is one of the key aspects of product application and development. Some domestic manufacturers have begun using microcomputer-based testing systems to test the lifespan and other parameters of electromagnetic relays. However, this method estimates various reliability characteristics of products under normal operating conditions using general life testing methods. This approach is unsuitable for products with exceptionally long lifespans because it requires a lengthy testing period, and sometimes new products are designed before the life test can be completed, rendering older products obsolete. To address these issues, this paper proposes an accelerated life testing method—increasing stress and shortening testing time—based on life testing principles. II. Accelerated Life Testing Analysis Accelerated life testing involves artificially increasing test stress (such as thermal stress, wet stress, and mechanical stress) to accelerate component failure and shorten testing time, allowing for the prediction of lifespan characteristics under normal (i.e., rated or actual use) conditions within a shorter timeframe. The analytical method for accelerated life testing primarily utilizes component failure data and uses accelerated life curves to calculate the reliability lifespan characteristics of the batch of components under normal conditions. This type of testing method is widely used, mainly because of its short research cycle, which significantly reduces testing time. Accelerated life testing typically falls into three categories: (i) Constant stress accelerated life testing, which involves applying a constant stress level to the test product sample throughout the test. To accelerate failure and shorten the test time, the stress in each group of life tests is required to be higher than the stress under normal operating conditions. This simulates actual environmental factors and appropriately increases the stress level without altering the product failure mechanism, achieving results similar to long-term field storage tests in a short period. (ii) Step stress accelerated life testing, which involves gradually increasing stress on the test sample over time in stages until a large number of failures occur. (iii) Sequential stress accelerated life testing, which involves increasing stress on the test product sample at a constant rate over time until a large number of failures occur. In this method, products are not grouped, stress is not graded, and stress increases at a constant rate until a certain number of failures occur. The applied stress level increases at a constant rate over time, therefore, this test requires specialized equipment. Among these three types of accelerated life testing, constant stress accelerated life testing is more mature, easier to process data, and has higher extrapolation accuracy. Although this type of test is not the shortest, it still shortens the time considerably compared to general life tests, making it more commonly used. Many factors affect the lifespan of electromagnetic relays. For example, during storage, the various performance characteristics of the product are greatly affected by environmental factors such as temperature, humidity, light, corrosion, oxidation, cracking, softening, mold, and crystallization. Non-metallic materials, in particular, exhibit significant aging under varying temperature, humidity, and climate conditions; the longer the storage time, the more severe the aging, even leading to failure and scrapping. Temperature has a particularly significant impact on the lifespan of electromagnetic relays. Therefore, this test device uses accelerated stress in constant temperature stress accelerated life testing, that is, placing the test sample at a specific temperature and measuring the test data under this environment. III. Hardware Design The electromagnetic relay life accelerated testing device consists of three parts: a test control cabinet, a load, and an automatic temperature-controlled chamber (providing accelerated stress). The control cabinet, composed of an industrial computer, data acquisition and control circuit, and coil drive circuit, is the main part of the design. The hardware circuit structure block diagram is shown in Figure 1. The data acquisition and control circuit mainly includes a decoding circuit, a data acquisition circuit, and a comparison voltage setting circuit. The industrial control computer transmits the address to the decoder via the address bus. The decoding circuit selects the chip corresponding to the address for read and write operations. The data acquisition circuit works by testing the sample contact voltage and comparing it with a comparison voltage. A voltage comparator compares the voltages, and the resulting contact state is transmitted to the contact state register via an optocoupler. When performing a "read" operation, the data in the register is transmitted to the data bus via a buffer; simultaneously, the data acquisition card acquires the actual voltage value on the contact and sends it to the industrial control computer for storage and display. The comparison voltage setting circuit works by selecting a latch through the decoding circuit, performing a "write" operation, and sending its output digital signal to the D/A converter via an optocoupler to generate the comparison voltage required for the test. The coil drive circuit controls the on/off operation of the electromagnetic relay coil by controlling the output of the industrial control computer, allowing it to close or open to simulate normal operating conditions. This part of the circuit consists of a DC power supply, a solid-state relay, and an electromagnetic relay coil. The DC power supply provides the electrical signal applied to the coil, and the solid-state relay controls the on/off operation of the DC power supply applied to the electromagnetic relay coil. When a test sample fails, operation on that sample needs to be stopped immediately. This can be achieved simply by not providing a control signal to the solid-state relay. If no electrical signal is provided to the solid-state relay during subsequent tests, the test sample will not operate again, thus shielding the failed test sample. IV. Application Software Module Design With the rapid development of computer multimedia technology and graphics and image technology, visual programming has gained widespread attention. More and more computer professionals and non-professionals are beginning to study and apply visual technology. Supporting visual programming typically requires a corresponding visual development environment. Visual C++ is an integrated development environment (IDE) launched by Microsoft that supports visual programming. Based on years of use and continuous improvement, it is a development environment for applications, services, and controls on the Win 95 and later platforms. It provides powerful wizard tools (MFC App Wizard, Class Wizard), supports multi-threaded application development, can directly embed assembly language to control hardware, and can easily operate on surfaces and ports with fast execution speed. This experimental system uses the MFC class library in Visual C++ 6.0 to develop the user interface. The system application software consists of six functional modules: parameter setting and initialization module, information display module, coil on/off control module, data acquisition module, data processing module, and failure judgment and processing module, as shown in Figure 2. Parameter setting involves recording parameters such as the model of the test sample, tester information, and test time before the test begins, preparing for displaying failure status and printing relevant information. System initialization mainly involves matching the coil and contacts to determine if a test sample is present, thereby determining whether to drive the corresponding coil; recording the numbers to correctly determine if the test sample has failed and processing the data; and determining the comparison voltage value based on the data provided in the parameter setting module. The information display module displays test-related information for real-time monitoring, including contact status display, failure status display, test sample information display, tester information, and test date display. The coil on/off control module has two functions: first, it controls the on/off operation of the test sample coils based on the test sample installation status obtained during system initialization; that is, it energizes circuits with test samples and de-energizes circuits without test samples, thus controlling the on/off operation of all test sample coils; second, it controls the on/off operation of individual test sample coils, mainly for shielding test samples that have reached the specified number of failures. The data acquisition module is the core of the system, realizing the system's testing functions. During the test, it collects parameters such as contact voltage drop, contact opening voltage, contact closing time, and contact opening time, providing necessary test data for the information display module, failure and handling module, and data processing module. The failure judgment and handling module detects the contact information in the contact status register and determines whether it is a failure message. Based on the on/off state of the test sample coil and the output level after comparing the voltage between the contacts on the data line with the comparison signal voltage, the system determines whether the test operation is normal. Simultaneously, it identifies the type of failure, records the failure type, the time of failure (or the number of times the electromagnetic relay actuated), the test sample number, the contact number, and the number of failures for that test sample. The data processing module includes data analysis (using one or more of univariate linear regression analysis, exponential regression analysis, weighted exponential regression analysis, least squares method, and grey theory analysis to calculate the lifespan of the electromagnetic relay under normal stress conditions), storage of test results and data, printing of test sample parameters, test results and data, measurement personnel information, and measurement date, etc. V. Conclusion This paper, based on the principle of accelerated life testing and the environmental factors affecting the lifespan of electromagnetic relays, uses temperature as the accelerating stress in the accelerated test and adopts a constant stress accelerated test method. It designs the hardware circuit of an electromagnetic relay accelerated life test system and develops related application software using VC++ 6.0, thus providing a fast and effective test system for accurately predicting the lifespan of electromagnetic relays.