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0 Introduction For chemical enterprises, operations are characterized by the presence of hazardous and toxic substances, as well as flammable and explosive materials, along with high pressures and temperatures. It is evident that most of the production facilities in such enterprises operate in dangerous environments with potential for explosions; therefore, safe production is a fundamental requirement for the smooth operation of these enterprises. Achieving safe production requires not only an improvement in management awareness and the enhancement of management practices, but also timely maintenance of the numerous electrical devices used in enterprises. It is necessary to check whether these devices are functioning properly, whether their performance remains good, and whether they are showing signs of aging. In particular, the aging of electrical devices in enterprises is a crucial aspect of electrical management in chemical industries; a failure in just one component can lead to serious safety issues that affect the stability of the entire system. To improve the management and risk prevention in chemical enterprises, it is essential to have a thorough understanding of the aging issue of electrical equipment within these enterprises, and to take appropriate measures based on the characteristics of this problem, thereby ensuring the safety of construction and production processes in such enterprises. 1 The importance of implementing protection measures for electrical equipment in chemical enterprises To ensure the stable and safe operation of electrical equipment and to prevent damage to it, it is necessary to provide strict protection for such equipment. Inspection and diagnosis of the electrical equipment should serve as a basis for adopting appropriate strategies for its protection and maintenance. Furthermore, it is necessary to ensure that the methods used for measuring and testing various operational parameters in the electrical equipment of chemical plants are highly accurate, and that the quality of the testing equipment meets the required standards for precision. At the same time, it is also necessary to take into account the actual conditions, fully understand and grasp the operating status of the electrical equipment in chemical enterprises, so as to ensure the normal operation of these enterprises’ production activities and thereby further improve their production efficiency. At present, with economic growth and social progress, the load and stress imposed on electrical equipment in chemical enterprises have a significant impact on equipment failures. To ensure the more efficient, stable, and safe operation of electrical equipment in chemical enterprises, it is urgently necessary for such enterprises to adopt reasonable and scientific measures to provide effective protection for this equipment. 2 Protection Configuration for Electrical Equipment in Chemical Enterprises 2.1 Protection Configuration Required for Main Transformers (1) Protection configuration for differential quick-break protection. If either differential current exceeds the setting value for differential quick-break protection, the output relay is activated immediately, causing the circuit breakers on both sides of the transformer to trip, thereby protecting the transformer itself. (2) Protection configuration for the high-pressure backside. Usually, a repressurization overcurrent section is required, with repressurization locking in the overcurrent section and zero sequence in the overcurrent third section. (3) Protection configuration for low-voltage backup. Usually, overcurrent stages 1 and 2 for repressurization are required, and repressurization locking is carried out in overcurrent stages 1 and 2. 2.2 Protection configurations for switching equipment Since the incoming switch (110KV) in chemical plants falls under the control of the higher-level power supply system, and the values determined are set by the higher-level power supply authorities based on the actual conditions of the power supply system, protections such as grounding and phase-to-phase distance protection, longitudinal differential protection, phase current overload protection, and zero-sequence direction protection can generally be implemented. 2.3 Protection Configuration for Oil-Immersed and Dry-Type Distribution Transformers First, there is an overcurrent stage that is equivalent to the instantaneous fault protection stage; the current setting is determined in order to avoid the transformer’s inrush current. In this case, the time setting can be set to zero seconds for instantaneous fault protection, with the aim of protecting the transformer against short circuits. Second, there is an overcurrent second stage, which imposes a timing limit on the overcurrent phase and is mainly used for overload conditions. Third, over-temperature tripping is adopted. For dry-type transformers, Class F insulation usually trips at 150°C ； As for oil-immersed transformers, tripping usually occurs at 95°C. Fourthly, heavy gas tripping is employed; this is mainly used in oil-filled power distribution transformers, and it serves to protect against internal faults such as inter-phase short circuits and turn-to-turn short circuits in the transformer. Fifth, overload alarm: An alarm signal is generated when the rated current is exceeded and a time delay occurs. 2.4 Bus Coupling Protection Configuration First, protection is provided for short circuits. When the busbar circuit breaker is closed, if the protection does not activate, it automatically shuts down and waits for the next closing of the busbar circuit breaker; this is done to protect against faults caused by zero-sequence overcurrent and inter-phase overcurrent. Second, implement long-duration charging protection. In other words, it provides protection against overload of the busbar, as well as protection against zero-sequence overcurrent and inter-phase overcurrent. If the time difference in the system is not significant, protection against long charging is not necessary at this time. Third, implement automatic backup switching. In chemical plants, the single-bus sectionalization system is very common; if two sections of the bus are operating in a sectionalized manner, automatic backup switching can be implemented. Generally, the automatic transfer switch has only two modes: transferring to the busbar in case of a first-stage or second-stage power failure. 3 Strategies for the Protection Configuration of Electrical Equipment in Chemical Enterprises Generally speaking, if electrical equipment in chemical enterprises ages, it leads to a reduction in their reliability, safety, and stability, which in turn increases operational costs and production expenses. If the aging reaches a severe level without replacement or timely maintenance, it can very easily result in safety accidents. Therefore, in order to prevent electrical equipment from suffering from premature aging and to improve its operational performance, appropriate measures for maintenance and care should be taken during its use. 3.1 Enhance the safety awareness of relevant personnel regarding the installation of protective measures for electrical equipment. To ensure the safe operation of chemical enterprises, it is essential to first strengthen the safety awareness of these personnel; otherwise, nothing can be carried out or implemented successfully. Therefore, to provide protection for the electrical equipment in chemical enterprises, it is first necessary to enhance the safety awareness of the enterprise’s management and increase their focus on the protection of such electrical equipment ； Secondly, it is important to focus on improving the competence of equipment maintenance personnel, helping them understand their job responsibilities and roles. They should not only be those who repair the equipment, but also serve as guardians of its safe operation ； Third, it is necessary to establish institutional procedures and operational standards so that the relevant staff have clear guidelines to follow in their work. 3.2 Regular inspection of electrical equipment By conducting timely inspections and maintenance of electrical equipment, it is possible to detect faults and problems that arise during its operation. Especially after the equipment has been in use for a while, its characteristics will inevitably change to some extent; therefore, it is even more necessary to carry out regular checks and maintenance, so that issues can be identified promptly and resolved as soon as possible. Specifically, electrical equipment can be inspected from several aspects. Firstly, it is necessary to regularly collect parameters related to the operating conditions of electrical equipment as well as parameters for performance evaluation, so as to carry out more targeted inspections, guidance, and maintenance of such equipment. Second, it is necessary to analyze and manage the data obtained from inspections, so as to predict the performance trends of electrical equipment based on that data. 3.3 Strengthen safety inspections of electrical equipment In chemical enterprises, some failures may occur due to the aging of certain electrical components; therefore, it is necessary to be vigilant when such failures arise. It is important to analyze promptly the reasons for any damage that might result from component replacements, to determine whether there are any safety hazards involved. To ensure the safe operation of electrical equipment in chemical enterprises and to enable proper maintenance and inspection to be carried out, thereby guaranteeing stable operation of such equipment throughout its lifespan, it is essential to conduct regular safety inspections of the electrical equipment. Generally speaking, safety accidents involving electrical equipment are mainly composed of three stages: normal operation, the existence of hidden hazards, and the occurrence of the accident itself. Therefore, it is necessary to carry out timely maintenance and inspection of electrical equipment in chemical enterprises, in order to eliminate potential safety hazards before accidents occur. This requires that those in charge of electrical equipment have a strong sense of responsibility when managing such equipment, be clear about their work attitude, conduct thorough inspections of the electrical equipment, and possess sharp analytical skills. They need to have a deep understanding of the equipment’s structure, operating conditions, and parameters, so as to identify potential problems before accidents occur and prevent safety hazards from escalating and leading to incidents. Furthermore, Haiying ensures that the relevant operators carry out their tasks in strict accordance with the specifications, in order to avoid problems arising from improper operations. 3.4 Ensure proper isolation and protection of electrical equipment, as well as carry out dust removal and cleaning tasks. During the production process in chemical enterprises, it is inevitable that there will be some chemical gases or dust particles present. In such an environment, electrical equipment is more likely to be affected in its operation; therefore, it is essential to pay attention to cleaning these devices and providing them with proper isolation and protection. This helps to prevent short circuits during operation, improves the performance of the equipment, and delays the corrosion of its insulation layers. 4 Conclusion In summary, for chemical enterprises, to ensure the safe, stable, and reliable operation of electrical equipment, it is essential to pay attention to providing appropriate protection measures for such equipment and to raise the safety awareness of relevant personnel. This will in turn contribute to the safe operation of the entire enterprise as well as an improvement in its economic performance.