MDmax ST High-Safety Low-Voltage Switchgear

MDmax ST High-Safety Low-Voltage Switchgear

MDmax ST is an ABB MDmax ST TTA Low-Voltage Switchgear, a fully type-tested (TTA) modular low-voltage switchgear system developed by ABB. It complies with IEC 61439-2 and GB/T 7251.2 standards.

Built on a 25 mm standardized modular G-profile aluminum-zinc coated steel frame, the system integrates four core advantages: enhanced safety protection, digital intelligent power distribution, high-density modular design, and long-term durability.

The product covers a current range from 400A to 6300A, and supports flexible configurations including incoming feeders, outgoing feeders, reactive power compensation, and motor control integration. It is widely applied in industrial manufacturing, renewable energy, municipal infrastructure, data centers, and commercial buildings, making it a mainstream solution for mid-to-high-end low-voltage power distribution systems.

Advantages and Features

• Four-Chamber Independent Compartmentalization Structure: The system features complete physical isolation between the busbar compartment, functional unit compartment, cable compartment, and auxiliary/control wiring compartment. Separation levels from Form 2b to Form 4b are available. A fault in a single circuit is effectively contained, preventing propagation to adjacent compartments.

• Drawer-Type Forced Mechanical Interlocking: Each drawer unit is equipped with three-position locking mechanisms (Service / Test / Isolated). The cabinet door cannot be opened when the circuit breaker is in the ON (closed) position. Operating handles can be fitted with external padlocks, effectively preventing unsafe energized insertion or withdrawal operations.

• High Short-Circuit Withstand Capability: The main busbar is designed for a short-time withstand current up to 100 kA/1s and a peak withstand current up to 220 kA. An optional arc flash protection system is available to enable rapid pressure relief and arc extinction under internal arc fault conditions.

• Multi-Level Dustproof and Waterproof Protection: The standard enclosure protection degree is IP30, with optional upgrades to IP40 or IP54. A full-perimeter sealing gasket ensures enhanced protection, making the system suitable for humid environments, dusty conditions, and mildly corrosive industrial applications.

General Data