Summary
- Starline T5 DoubleBar supports continuous current ratings up to 2,000A.
- A new High-Capacity Plug-In Unit offers branch connections rated up to 250A.
- Current ratings do not alone establish usable rack power, which depends on voltage, configuration and protection.
Legrand has introduced a Starline busway system rated for continuous currents up to 2,000A, expanding its electrical distribution range for data centres installing increasingly power-intensive AI and high-performance computing racks.
The T5 DoubleBar uses a parallel conductor arrangement within the manufacturer’s open-channel track busway architecture. It is designed to increase the current that can be carried along an overhead distribution route while supporting plug-in branch connections to computing equipment below.
Legrand has also introduced a High-Capacity Plug-In Unit capable of supporting configurations up to 250A. The unit is intended for demanding rack-level connections where several smaller taps might otherwise be required.
These ratings address a practical constraint in computing rooms. As rack power increases, electrical engineers must provide suitable supply routes without consuming excessive overhead space needed for cooling pipework, network cables, cable trays and other services.
A busway encloses conductors in a system that allows connections at defined points, using compatible units to distribute electricity from upstream equipment. Compared with a design based entirely on individually routed cables, a busway can allow some modifications to branch positions and ratings without replacing the entire supply route.
Whether a particular change is permitted depends on the installed equipment and manufacturer’s procedures. A reconfigurable distribution system does not mean any electrical alteration can be made safely while energised or without checking the effect on upstream protection.
The DoubleBar design uses two parallel conductor paths to provide higher current capacity than smaller configurations. Legrand describes the system as suitable for rack deployments above 100kW and for dense AI infrastructure where large power feeders must be accommodated close to the equipment.
The published 2,000A figure is a current rating, not a standalone power figure in kilowatts. Usable electrical power depends on voltage, phase arrangement, power factor for alternating-current supplies and the equipment’s permitted operating conditions.
A three-phase AC connection and a higher-voltage DC distribution system can therefore have very different power characteristics even if the conductor current is identical. Electrical designers must specify the complete circuit before comparing the amount of usable rack power.
Legrand’s technical information describes compatibility with future power architectures, including DC installations up to 1,000V. That is a stated capability of relevant configurations; it should not be interpreted as certification of every product combination for every AC or DC system.
Direct-current distribution introduces different fault behaviour from conventional alternating-current designs. Protection systems must be able to interrupt faults at the available voltage and prospective current, while insulation, switching equipment and installation methods must suit the application.
The manufacturer lists UL 857 and IEC 61439-6 among applicable standards, along with certification and marking for the system. The site engineer still needs to verify precisely which configuration and intended use are supported by the relevant documentation.
Thermal performance is another consideration. Current passing through conductors produces heat, and the ability of a busway to carry its rated load depends on the design and expected installation environment. Ambient temperature, conductor grouping and the available space for heat dissipation can influence equipment selection.
The 250A plug-in unit is presented as a companion product for the higher-capacity system. Its purpose is to bring a larger branch supply closer to a high-demand rack without requiring multiple lower-current connections solely to deliver enough capacity.
A high-current branch must still have suitable circuit protection and a cable or connection assembly rated for its load. The busway’s rating cannot compensate for undersized upstream switchgear, transformers, power supplies or a constrained external grid connection.
The design also needs sufficient space for inspection and future maintenance, because a higher rated conductor may remain difficult to service if adjacent mechanical and network infrastructure obstruct access.
In existing data centres, upgrading distribution may also involve structural supports, available clearances, outage planning and coordination with liquid cooling infrastructure. The physical ability to install the new system is separate from the question of whether additional electricity is available to use it.
Legrand’s launch establishes a new product specification but does not identify independently verified reductions in installation time, capital cost or operational losses at a deployed site. Those results would depend on the project design and comparison method.
The product expands the electrical distribution options available to new AI facilities. Its practical value will be determined by how engineers coordinate current ratings, voltage, protection, equipment layout and the actual capacity available at each stage of commissioning.
