Product Introduction:

MNS low-voltage withdrawable switchgear is a combined cabinet type assembled in the factory using standard modules (FBA).

MNS low-voltage withdrawable switchgear is suitable for power plants, substations, petrochemical facilities, metallurgical rolling mills, transportation and energy, light industry and textile enterprises, residential communities, high-rise buildings, and other applications. It is used in AC 50-60 Hz power systems with rated operating voltage of AC 0.4 kV for power conversion, distribution, and control by distribution equipment.

Product Features:

I. Structural Design Features

1. Modular Combination Frame

Uses a combination of C-shaped profiles and G-shaped cross beams, with 25 mm (E=25 mm) as the basic module. Assembly is flexible and highly rigid, allowing flexible combination and splicing according to actual needs. All components are galvanized for corrosion protection and connected with high-strength bolts. The cabinet has high precision and good earthing continuity, effectively improving service life and operating stability.

2. Compact and Efficient Layout

Space utilization is extremely high, allowing a large number of functional units to be integrated within limited cabinet volume and saving installation space. The interior adopts a fully segregated three-zone design, with independent horizontal busbar compartment, functional unit (drawer) compartment, and cable compartment. This effectively prevents fault propagation, reduces cross-fault risk, and improves operating safety.

3. Flexible Incoming and Outgoing Cable Arrangements

Supports multiple wiring schemes including top-in/top-out, top-in/bottom-out, bottom-in/top-out, and bottom-in/bottom-out. Options can be selected flexibly according to site installation conditions and wiring requirements, adapting to installation needs under different working conditions without additional cabinet modification and reducing construction difficulty.

II. Functional Unit Features

1. Withdrawable Drawer Units

Drawer units adopt a standard modular design and are available in multiple sizes such as 1/2, 1, 2, 3, and 6E. Drawers of the same size are fully interchangeable, facilitating later maintenance, replacement, and expansion. The units have three-position mechanical interlocking, clearly distinguishing connected, test, and isolated working positions. Clear position indication and reliable locking devices effectively prevent misoperation and protect operators. A single-handle operating design integrates circuit breaker opening/closing with drawer racking in/out, making operation convenient and status easy to identify.

2. Mixed Assembly Capability

Supports arbitrary mixed installation of drawer units, fixed units, and air circuit breaker cabinets. The system offers extremely high configuration flexibility, enabling different types of functional units to be combined according to the actual needs of the distribution system, meeting diverse distribution-control requirements and customized configurations for different scenarios.

III. Safety and Protection Performance

1. High Protection Rating

The standard protection rating can reach IP30-IP42, and higher protection ratings can be customized for different environments such as dusty or humid conditions. This effectively resists ingress of external dust and foreign matter and protects internal electrical components. Cabinet doors can be fitted with padlocks for secure locking, further improving equipment safety and preventing unauthorized operation.

2. Arc-Resistance and Flame-Retardant Design

The busbar system is enclosed with high-strength flame-retardant insulating plates and provides excellent fault-arc resistance, effectively suppressing arc propagation and reducing harm to equipment and personnel. Flame-retardant engineering plastics are widely used in the cabinet body and internal components, providing excellent flame-retardant performance, effectively suppressing internal arcing, reducing fire risk, and ensuring long-term safe operation.

3. Reliable Dynamic and Thermal Stability

The main busbar peak withstand current can reach up to 105 kA, and the rated short-time withstand current (1 s) can reach up to 50 kA. Strong short-circuit breaking capability enables the system to withstand impacts caused by short-circuit faults and ensures distribution system stability. High-current circuits use anti-eddy-current (stainless steel) design to avoid local overheating caused by eddy currents, extending equipment service life and improving operating stability.

IV. Electrical Performance Parameters

Rated voltage: AC 400 V and below; insulation voltage: 690 V.

Rated current: main busbar up to 4000 A; drawer unit up to 630 A.

Applicable frequency: 50/60 Hz.

V. Summary of Core Advantages

High universality: components have a high degree of standardization, spare parts are easy to procure, maintenance cost is low, and different brands of electrical components can be accommodated.

Convenient maintenance: faulty drawers can be hot-swapped online without power outage, greatly shortening fault handling time and enabling rapid power restoration.

Good expandability: modular structural design facilitates later capacity expansion and retrofit, supports intelligent upgrades, and adapts to the long-term development needs of distribution systems.

Wide application: suitable for various low-voltage distribution scenarios such as power plants, petrochemical facilities, metallurgy, buildings, data centers, and rail transit, meeting diverse operating condition requirements.