Electric Power Substation Safety Inspection

A prefabricated box-type substation—commonly referred to as a modular substation—is an integrated power distribution solution that undergoes full prefabrication in a factory setting. Designed for both indoor and outdoor deployment, this compact system integrates core functions including power distribution, transformer step-down, and low-voltage power supply into a single unit. Housed within a fully enclosed steel structure cabinet, the substation is engineered to meet stringent environmental protection standards: it features moisture resistance, rust prevention, dust proofing, rodent proofing, fire resistance, anti-theft capabilities, and thermal insulation. Unlike traditional civil engineering substations, this modular design offers unparalleled flexibility and practicality, making it a preferred choice for urban power grid construction and renovation projects, as well as a groundbreaking innovation in the power distribution equipment sector.

One of the key advantages of box-type substations lies in their oil-free operation, which completely eliminates the risk of equipment leakage—a long-standing issue with conventional substations. However, as with any high-voltage electrical equipment, strict adherence to safety protocols is critical during inspection and maintenance to mitigate potential hazards. Below is a detailed overview of key safety considerations and best practices for box-type substation inspections.

To prevent low-voltage electric shock in AC and DC systems, rigorous pre-inspection checks and standardized operating procedures must be followed. Prior to disconnecting the test power supply, verify that the insulating cover of the test switch is intact and free from damage; only after confirming the power switch is fully disconnected can inspection work commence. A critical safety note: opening the secondary circuit of a current transformer (CT) under operation can generate dangerously high voltages, posing severe electric shock risks. Therefore, the permanent connections of CT secondary circuits must never be disconnected during inspections. When measuring fuses or voltage levels in transformer secondary circuits, operators must use insulated tools and wear certified insulating gloves to ensure personal safety. All operations should align with IEC 61936 or relevant national electrical safety standards to minimize risks.

Comprehensive electric shock prevention requires a systematic approach that covers pre-installation checks, on-site preparation, and real-time supervision. Before initiating any work, confirm the equipment nameplate, identification number, and operational parameters to ensure alignment with the work scope. Conduct a thorough assessment of the work area, including verifying the status of the power supply and ensuring all safety measures are in place. For cables and capacitors, phase-by-phase full discharge is mandatory to eliminate residual electrical charge that could cause unexpected shocks. Additionally, assigning dedicated monitoring personnel to oversee the entire inspection process is essential—these personnel should have a clear understanding of safety protocols and the authority to halt operations if potential hazards are identified.

Accidental contact with live components is a major safety risk during substation inspections, making strict access control a top priority. After withdrawing the trolley switch of the high-voltage switchgear, ensure the baffle covering live parts is securely closed and locked. Unauthorized opening of shutters or barriers protecting live equipment is strictly prohibited, as this can expose operators to lethal voltages. All personnel involved in inspection work must undergo regular safety training to recognize restricted areas and understand the consequences of non-compliance. Clear signage indicating live equipment zones should be prominently displayed throughout the substation to reinforce safety awareness.

Prefabricated box-type substations are versatile and widely used across various sectors, including residential communities, urban public power transformation projects, downtown commercial areas, and building-specific power supply systems. The selection of a suitable substation model depends on two key factors: the specific operating conditions (such as indoor/outdoor deployment, environmental temperature, and humidity levels) and the load capacity requirements of the application. During the design phase, engineers only need to finalize the main wiring diagram and external equipment configuration based on the substation’s basic functional requirements; the appropriate specifications and models of box-type substations can then be selected from the manufacturer’s product range. This streamlined design process significantly reduces project complexity and ensures compatibility between components.

A defining benefit of prefabricated box-type substations is their factory-integrated production and debugging process. All internal equipment—including transformers, switchgear, and protection devices—is fully installed, wired, and tested at the factory, eliminating the need for on-site assembly of individual components. This not only guarantees consistent product quality but also drastically shortens the overall project timeline compared to traditional civil engineering substations. On-site installation work is limited to core tasks such as cabinet positioning, inter-cabinet cable connection, output cable termination, protection setting verification, and system commissioning. From the completion of factory production to on-site installation and final commissioning, the entire process can be completed in just 5 to 8 days. This rapid deployment capability is particularly valuable for projects with tight schedules, such as emergency power supply upgrades or new urban development projects, as it minimizes downtime and accelerates the delivery of reliable power.

We are a high-tech enterprise specializing in the R&D, production, sales, and installation of power equipment. Our comprehensive product portfolio includes power transformers, prefabricated box-type substations, high and low-voltage complete sets of equipment, and special-purpose substations tailored for wind power and photovoltaic energy systems. With a strong commitment to technological innovation, our products boast technical performance that meets international advanced standards in the industry. To date, we have obtained 109 patents—including invention patents and utility model patents—covering key technologies in power conversion, energy efficiency optimization, and safety protection. Our quality management system is certified to ISO 9001, and our products have also passed CCC certification (China Compulsory Certification) and SGS certification, ensuring compliance with strict domestic and international quality and safety standards. We are dedicated to providing customers with reliable, efficient, and customized power solutions, supported by professional technical services and after-sales support throughout the project lifecycle.