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Five Major Issues in Electrical Installation and Their Solutions (I) Wiring Installation 1. Regular cracks appear in areas where the wiring is installed concealed； 2. Metal pipes must be equipped with a bonding ground wire; or, regardless of the material, they should all be welded together to form a bonding ground wire ； 3. No road boxes are provided for pipes passing through structural expansion joints and settlement joints, leaving potential safety hazards ； 4. Galvanized pipes are directly connected by sleeve fusion welding; the connection using sleeves is not very secure ； 5. The rigid and flexible pipes entering the box are not straight; they are packed together, and the lengths of their exposed parts are not appropriate. The steel pipes lack threading, and the PVC pipes have no locking elements” ； 6. The metal hose has come loose, and no grounding connection has been made. (II) Cable and busbar installation: 1. After installation, the cables are not labeled uniformly, and they are laid in a messy manner within the cable trench ； 2. The cable is not properly sealed after passing through the entry pipe ； 3. In the shaft, the cable openings are not properly sealed, and the brackets used to fix the cables vertically are too small and too soft, causing them to tilt downward ； 4. The joint surfaces of the busbars were not treated in accordance with the specification requirements; for example, when connecting copper and aluminum in humid environments, the copper conductors were not tin-plated, or although the copper conductors were tin-plated, no copper-aluminum transition plates or pins were used to connect them. Accidents are likely to occur after being powered on for a while. (III) Embedding of power distribution boxes, junction boxes, and ceiling fan hooks: 1. The power distribution boxes, junction boxes, and hooks are not installed according to the drawings; there are significant coordinate deviations, and the offsets for rows of lighting fixtures and ceiling fan hook boxes are large ； 2. The boxes and enclosures within the cast-in-place concrete walls and columns are tilted, with deep indentations; too many pipe ends extend into these boxes and enclosures. The box is secured with small fasteners; to prevent it from shifting due to vibrations or concrete slurry from entering it, the box undergoes anti-rust and anti-corrosion treatment. (IV) Lightning protection grounding: 1. The lightning protection strips are installed using ordinary steel bars; the connections between the strips as well as those to the down conductors are made by butt welding or single-sided welding. The overlap length is insufficient, and the weld joints are severely corroded ； 2. The metal components on the roof are not connected to a lightning protection system; metal pipes are used in place of the grounding PE wire for equipotential bonding, and the cross-grounding wires in the cable trays have insufficient diameter ； 3. The equipment’s grounding bar is not directly connected to the main grounding wire ； 4. The spacing between supports is too large, resulting in strip-shaped deformation and support detachment; the corners and downward leads form sharp angles, and the spacing between the downward leads is excessive ； 5. When a TN—S grounding system is used in multi-story buildings, no repeated grounding is provided at the incoming line of the main distribution box, etc. (5) Qualifications of installers: Recently, a common issue among the construction teams working on electrical installation projects in civil buildings is that the qualifications of the installers are not high enough, falling short of the requirements of modern electrical engineering. Although they have considerable experience in on-site construction, they lack professional theoretical knowledge. Their strength lies in operational skills, but they have insufficient understanding of technical aspects and construction drawings. For example, in the main power distribution system of a 10-story building, the diameter of the main cables is required to remain constant from the first floor to the sixth floor. However, many workers believe that the diameter of the cables from the first floor to the sixth floor can be reduced step by step according to changes in load, which is not allowed according to the regulations (it does not comply with Articles 6.3.4 and 6.3.5 of the \"Code for Design of Low-Voltage Power Distribution\" GB50054-2011). Such practices pose safety risks to the use of the building. II. Methods for Preventing and Resolving Problems During Building Electrical Installation (1) Improving the design and installation of distribution boxes Distribution boxes serve as the direct controllers of electrical loads at the site. To ensure the proper operation of power and lighting loads in electrical engineering, the performance of the components within the distribution box is of critical importance. In engineering projects, the component models in distribution boxes are complex and their quantities are large; some distribution boxes contain equipment from low-voltage specialties such as building management and fire protection systems. The electrical system involves various specialties, each with its own characteristics, and design work is often constrained by the requirements of these different specialties, which leads to additional design modifications. As a result, there are many changes to the equipment and circuits within the distribution boxes. If the construction contractor orders materials solely based on the construction drawings, ignoring the revision documents, and focuses only on equipment installation during setup without conducting a thorough technical review, the requirements related to the specialized functions will not be met. Therefore, the construction contractor should check each distribution box on site in accordance with the design modification notices, and correct any errors such as switches having an excessive or insufficient capacity, or an inadequate number of circuits. Furthermore, the coordination between electrical equipment and circuit protection mechanisms at different levels is quite strict; selectivity is required. If these requirements are not met, it can lead to various problems such as unstable system operation, poor power supply reliability, and an expansion of the scope of accidents. Therefore, electrical design and construction must be carried out in strict accordance with current regulatory standards in order to reduce the risk of electrical accidents. (II) Lightning protection and grounding measures: Strengthen skill training for welders, ensuring that the welds at the joints are full, continuous, and smooth and even; special attention should be given to training for more challenging welding methods such as butt welding and overhead welding. Enhance the sense of responsibility among managers and welders, promptly repair any defective welds, remove slag in a timely manner, and apply anti-rust paint (above the ground level) or asphalt (below the ground level) for corrosion protection. In accordance with the relevant construction and acceptance specifications, the connection of lightning protection down conductors shall be made by lap welding, with the lap length being 6 times the diameter of the round steel; therefore, deformed steel bars should not be used as substitute for round steel as the lap reinforcement. Furthermore, for the main reinforcement bars that serve as downcomers, if butt welding is used during civil construction, an additional lap bar should be added at the welded joint in accordance with regulations, and the cross-section of this lap bar must meet the requirements specified in the codes. (III) Quality management before the construction of building electrical installation projects: Installers should carry out preliminary preparations prior to the installation work, based on the specific conditions of the electrical installation project to be carried out, in order to facilitate the proper execution of the building electrical installation tasks. This is specifically reflected in: 1. Contract management prior to installation and construction. The construction contractor shall, based on the construction design drawings and relevant change documents, as well as various subjective and objective factors such as the owner’s requirements, evaluate the contract’s provisions regarding construction methods, equipment usage, material supply, schedule targets, personnel allocation, and cost expenditures. They must prepare a reasonable construction budget and make accurate estimates and plans for the associated costs. 2. Management of materials and equipment prior to installation work. Material and equipment management is a prerequisite and foundation for installation projects, encompassing the procurement, inspection, labeling, storage, use, and recycling of materials and equipment. When purchasing relevant materials and equipment, it is necessary to assess the qualifications and production capabilities of the manufacturers to ensure that sufficient quantities of the materials and equipment required for construction are available on time. Request from the manufacturers relevant documents such as 3C certification and quality certificates, and organize professional technicians to inspect the purchased materials and equipment; return any products that fail the inspection, and reinspect those whose quality or compliance is in question. (IV) Quality management during the construction of building electrical installation projects 1. Organizational management during installation work. Organizational management in electrical installation projects consists of two parts: internal coordination organizational management and external coordination organizational management. Develop a reasonable management and organizational plan to coordinate the arrival times of installers, technicians, managers, and commissioning staff throughout the project timeline, thereby reducing unnecessary costs associated with manual management. Clarify responsibilities, organize close coordination between construction progress management and other specialized contractors, establish communication channels for timely feedback and information exchange, pay attention to resolving differences of opinion and conflicts that arise during construction management, and ensure that electrical installation work is completed to the required standard and quality. 2. Progress management during installation and construction. During the construction period, aspects such as equipment supply, personnel allocation, and the timing of construction activities all require coordination and control through progress management. The construction unit shall break down the entire installation project in accordance with the project’s deadline requirements, and prepare project progress plans for different time periods, such as daily plans, weekly plans, monthly plans, and so on. Identify the appropriate construction teams and responsible persons, establish a reward and punishment system, and reward those who exceed their targets while punishing those who fail to meet them. Ensure that the building electrical installation work is completed on schedule. 3. Interface management during installation and construction. Interface management during the installation process refers primarily to the coordination and division of responsibilities among electrical installation work, various sub-projects, and other construction tasks at the interface level. For example, when electrical equipment is integrated with a building’s intelligent management system, due to the large number of interfaces involved, it is common for the supervisors of each sub-system to hold regular coordination meetings in order to manage things effectively, making adjustments, coordinating efforts, and keeping records through written reports. 4. Personnel management during installation and construction. The quality of electrical installation work has a direct impact on the usability of construction projects. In the management of construction quality, construction units should establish a comprehensive quality inspection system for their workers, implement a quality target responsibility system, and assign quality responsibilities to specific individuals. 5. Carry out supervision and inspection of installation quality. The construction party must strictly use electrical equipment that meets **safety standards** as specified in the design, for construction and installation purposes. Establish relevant quality supervision rules and regulations to prevent practices such as cutting corners and using inferior equipment. (5) Quality management during the completion phase of building electrical installation projects: The construction and installation units must cooperate with the inspection teams to carry out the acceptance process. They should conduct inspections and tests of the electrical installation work in accordance with the current standards for electrical installation projects, feasibility reports, equipment technical specifications, as well as the objectives set for the overall construction project. Once all requirements are met, all relevant construction and installation documents shall be sealed and archived. (VI) Hire construction units with the necessary qualifications for installation, and provide timely training for the installation personnel. The construction unit shall strictly follow the provisions of **relevant rules and regulations** when installing building electrical systems ； Hire professionals to provide regular training for the installation crew, so that they can fully understand and master the installation of building electrical system equipment in the electrical field, as well as the installation principles for various electrical systems used for fire protection and construction purposes. They should also keep up to date with new technologies, new processes, and new products in the electrical field and apply them in the installation process.