High-Voltage Switchgear Series

A: Product Overview

The LWX375-550 Metal-Enclosed Switchgear is a compact, high-performance 12kV draw-out switchgear purpose-built for modern power distribution projects where installation space is extremely limited.. high-performance 12kV draw-out switchgear purpose-built for modern power distribution projects where installation space is extremely limited. As one of the smallest form-factor centrally-disconnected switchgears on the market, it combines cutting-edge APG solid insulation and silicone rubber sealing technology to deliver industry-leading insulation performance, even at altitudes up to 3000 meters.

Designed for 3–10kV three-phase AC 50Hz single busbar and busbar-segmented systems, this switchgear serves as a critical control, protection, and monitoring solution for a wide range of applications. From power plant generator feeders and industrial facility distribution panels to urban substations and large motor starting circuits, the LWX375~550 series adapts seamlessly to diverse power infrastructure needs.

Engineered to meet GB3906 standards, the switchgear features a modular structure divided into four independent compartments, with an IP4X enclosure rating that ensures safety against accidental contact with live parts. Its front-access design allows for all installation, commissioning, and maintenance operations without requiring rear clearance, enabling flexible back-to-back or double-row configurations to maximize floor space efficiency.

Built with precision CNC-machined aluminum-zinc steel plates and multi-folding processes, the cabinet body balances lightweight construction with exceptional mechanical strength and corrosion resistance. The series supports rated currents up to 2000A and short-circuit withstand currents up to 31.5kA, with insulation levels certified to 42kV power frequency and 75kV lightning impulse withstand voltages. Compliant with key standards including GB1984, GB/T11022, and GB/T14597, it operates reliably across a wide environmental range, from -45°C to +45°C, and up to 95% relative humidity.

The LWX375~550 series’ ultra-narrow 375–550mm width makes it ideal for space-constrained environments such as commercial buildings, hospitals, data centers, airports, and metro systems. It delivers robust performance, safety, and adaptability, making it a versatile choice for modern power distribution projects.

B: Model meaning

C: Conditions of Use

• Altitude: no more than 3000m;
• Ambient temperature: upper limit +45°C, lower limit-45°C;
• Relative humidity: daily average ≤95%.Monthly average≤90%;
• Seismic intensity: Anti-seismic;the seismic intensity does not exceed 8;
• Environmental conditions: The surrounding air should be free of corrosive or flammable gas,water vapor and otherobvious pollution;
• No serious pollution and frequent severe vibration.Strict design under severe conditions meets Class 1 requirements;
• When using in the normal environmental conditions specified in GB39o6, the user and the manufacturer negotiate.

D: Technical parameters

E: Application range

• Business, service industry ,shopping malls, shopping centers, office buildings, hospitals, playgrounds, residentialareas, basic and civil facilities;
• Industrial and mining enterprises: petrochemical, paper mil, cement plant, textile;
• Utilities and power stations: power plants, substations, switching houses, ring network power stations, main auxiliaryswitch stations;
• Transportation:airport, port, railway, subway;

F: Protection level

• The enclosure protection rating is : IP4X
• The main circuit protection level of the fully sealed busbar room and the cable interior is lP67
• The semi-insulated busbar room and the main circuit inside the cable are protected by IP2X
• When the circuit breaker door is open:IP2X

G: Use standard

• GB1984-2003″High Voltage AC Circuit Breaker”
• GB1985-2004″High Voltage AC Isolation Switch and Grounding Switch”
• GB3804-20043.6-40.5kV”High Voltage AC Load Switch”
• GB3906-2006 3.6-40.5KV”AC metal-enclosed switchgear and control equipment”
• GB16926-2009″AC load switch-fuse combination electric appliance”
• GB16927.1-1996″High Voltage Test Technology Part 1: General Test Requirements’
• DL/T402-2007″Technical Conditions for Ordering High Voltage AC Circuit Breakers”
  GB/T11022-2011″Common technical requirements for high-voltage switchgear and control equipment standards”
• GB/T14597-1993″Technical conditions for climatic environment at different altitudes of electrical products”
• GB311.1-1997″Insulation coordination of high voltage transmission and distribution equipment’

H: Structure diagram

The switchgear is designed according to the armored metal-enclosed switchgear in GB3906. The product is composedof two parts:the cabinet and the centrally-mounted extractable parts (ie the handcart).The cabinet is divided into fourseparate compartments with IP4X enclosure rating and IP2x protection for each compartment and breaker compartmentdoor. t has overhead access lines, cable entry and exit lines andother functional solutions.After being arranged andcombined, it can be a power distribution device of various schemes. The swtchgear can be installed, commissionedand maintained from the front, so it can be back-to-back and double-arranged and mounted, which improves thesafety, flexibility and floor space of the switchgear.

Shell: The parts of the switchgear cabinet are made of 2mm thick aluminum-zinc steel plate, processed by CNCmachine tool and adopt multi-folding process.In this way, the whole cabinet not only has high precision and strong anti-corrosion and anti-oxidation effects, but also adopts mutiple hemming process, so that the cabinet body is lighter inweight, higher in mechanical strength and beautiful in appearance than other similar equipment cabinets.The cabinetbody adopts an assembled structure and is connected by a rivet nut and a high-strength bolt. This makes the productioncycle short, the parts are versatile, and it is easy to organize production.

J: Related Products

If you are looking for other medium voltage switchgear equipment, you can check our KYN28A-12 armored removable switchgear and LWXt6 gas ring network cabinet. We provide complete 12kV~40.5kV high voltage cabinets with customized solutions for power plant, substation and industrial power distribution engineering

KYN28A-12 Type Armored Removable AC Metal-Enclosed Switchgear

LWXt6 Fully Insulated Compact Gas Ring Network Cabinet