Hager Main Distribution Board (MDB)

The Hager Main Distribution Board (MDB) is a type‑tested IEC 61439-2 low-voltage assembly engineered for building and commercial power distribution where predictable performance, selectivity and maintainability are required. At its core the assembly combines Hager Univers N modular enclosures with Hager h3+ moulded-case and air-magnetic protection devices, together with type‑tested busbar systems verified for temperature rise and short‑circuit withstand. The design envelope supports rated currents up to 6,300 A and short‑circuit ratings in the 50–100 kA (1 s) range, 690 V AC service, and Forms of Separation from 2b through 4b to meet segregation and maintenance transfer requirements per IEC 61439-1/2. Busbar systems are engineered and validated to IEC 61439 temperature-rise limits (measurement and calculation per the standard) using high‑conductivity copper with bolted/silver‑plated joints, calibrated bolted torque values and electroplated contact surfaces. Incoming protection is typically an ACB or high-capacity h3+ device with integrated electronic protection and optional metering; outgoing feeders use h3+ MCCBs or drawout units with adjustable thermal/magnetic tripping for discrimination. Electronic protection relays, residual current monitoring units and selective earth fault schemes are accommodated; metering and communications conform to IEC 62053 and support Modbus/IEC 61850 interfacing where required. Short‑circuit capability is achieved by combining certified Hager components compliant with IEC 60947 series and by assembly tests/verification per IEC 61439-1/2 (short‑circuit withstand and verification of mechanical integrity). Where higher availability and segregation are required, Form 4b assemblies permit full segregation of busbar, cable and functional units. IP ratings are configurable from IP31 to IP54 for indoor installations; for hazardous or Ex-rated environments the MDB can be adapted with Ex‑certified enclosures and components in accordance with IEC 60079 but typically requires project-specific certification and inspection. Compared against modular switchgear platforms such as Siemens SIVACON, ABB MNS and Rittal Prisma Set, the Hager Univers N + h3+ combination emphasizes compact building integration, simplified installation and full IEC 61439 type-test documentation suitable for commercial, healthcare, data center distribution, airport concourses and EV fast‑charging hubs. Factory assembly, witness testing and FAT documentation are supplied, including temperature rise reports, short‑circuit verification and routine electrical checks. For EPC contractors and facility managers specifying an MDB, Hager MDBs offer a pragmatic balance of certified componentry, tested busbar systems and modular enclosure adaptability, backed by engineering support for coordination studies, protective device settings and site acceptance testing.