I. Product Positioning and Application Scope
1. Electrical Specifications: Indoor three-phase AC 50Hz, rated voltage 40.5kV (corresponding to 35kV power grid), suitable for single busbar and single busbar sectioning systems; the core purpose is to receive, distribute electrical energy, control, protect and monitor circuits, and can be used in frequent operation conditions.
2. Typical Scenarios: Power plants, substations, large industrial and mining enterprises, high-rise buildings, rail transit, etc. 35kV distribution stations / distribution rooms.
3. Execution Standards: Comply with domestic and international authoritative standards such as GB/T 3906, GB/T 11022, DL/T 404 and IEC 62271-200, and have passed the type test of the National High Voltage Electrical Appliance Quality Inspection Center.
II. Core Technical Parameters (Common Configurations)
Rated Voltage: 40.5kV; Rated Frequency: 50Hz
Rated Current: 1250A/1600A/2000A
Rated Short-Circuit Breaking Current: 25kA/31.5kA/40kA
Rated Thermal Stability Current (4s): 25kA/31.5kA/40kA
Rated Dynamic Stability Current: 63kA/80kA
Power Frequency Withstand Voltage (1min): 95kV; Lightning Impulse Withstand Voltage: 185kV
Enclosure Protection Class: IP4X when closed (IP3X for some models), IP2X/IP3X when open for maintenance; equipped with a complete five-prevention interlock (preventing misoperation of circuit breakers, preventing load operation of disconnectors, preventing grounding wire connection when energized, preventing circuit breaker closing when grounding wire is connected, preventing entry into energized compartments by mistake)
III. Structure and Performance Features
1. Metal Armored Compartmentalization: The cabinet is of an assembled cold-rolled steel plate / aluminized zinc plate structure, divided into busbar compartment, trolley compartment, cable compartment, and relay instrument compartment. Each compartment is isolated by grounded metal plates and has an independent pressure release channel. The pressure of an accident arc can be discharged in a specific direction to prevent cabinet explosion and accident spread.
2. Floor-mounted Trolley: The circuit breaker trolley (can be equipped with vacuum / SF6 circuit breakers) adopts a floor-mounted design, with strong interchangeability and smooth and stable pushing. All operations can be completed with the cabinet door closed.
3. Composite Insulation Optimization: The main busbar uses insulating bushings / composite insulation, ensuring reliable isolation between cabinets; the cable compartment has ample space, facilitating connection of multiple cables and layout of grounding switches.
4. Intelligent Expansion: New models can integrate online monitoring (partial discharge, temperature, SF6 / vacuum degree), intelligent terminals and communication interfaces, supporting the IEC 61850 standard, and can be integrated into intelligent substation systems.
IV. Environmental Conditions Requirements
Indoor installation; altitude ≤ 1000m (customizable for high-altitude models)
Ambient Temperature: -15℃ to +40℃ (some models are low-temperature type at -25℃)
Relative Humidity: Daily average ≤ 95%, monthly average ≤ 90%; no fire, explosion, severe vibration or serious pollution / chemical corrosion

V. Application and Selection Tips
Flexible primary scheme: It can realize various wiring methods such as cable / overhead incoming and outgoing lines, busbar connection, PT / lightning arrester cabinets, isolation cabinets, etc.
Suitable for 35kV substations, power plant auxiliary power supply, and large industrial and mining enterprise distribution rooms with high requirements for power supply reliability, frequent operations, and centralized monitoring.
Selection should clearly define the rated current, breaking capacity, main wiring method, grounding switch configuration, secondary protection and communication interface requirements.