In most facilities, power distribution is something everyone assumes “just works” until a new project, expansion, or failure forces a closer look. Traditional cabling has served plants, offices, and data centres for decades, but rising loads, denser IT racks, and frequent layout changes are starting to expose its limits. At that point, decision-makers often hear about sandwich busbar trunking and wonder if it is simply a premium option or if it actually solves problems that cables cannot handle efficiently anymore.
The choice between traditional cable or a more recent approach with busbar trunking is about more than just the technology; it’s also about safety, potential expansion and total cost of ownership over many years. Understanding where each approach is strong, where it becomes a bottleneck, and which signals tell you it is time for a power distribution upgrade can help you move away from reactive fixes and towards a more planned, resilient infrastructure.
Why Your Power Distribution Approach Matters More Than Ever
Loads that used to be stable and predictable now change more often. High-density IT racks, new production lines, EV chargers, and automation equipment all put additional pressure on existing cable-based power distribution. A design that was adequate 10 years ago may be operating close to its limit today.
If the same cables are asked to carry more current, pass through more junctions, or stretch across more complex routing, the margin for error reduces. This is where the structured design of sandwich busbar trunking starts to look attractive: it is engineered from the start for known currents, short-circuit levels, and tap-off points, rather than growing organically with ad-hoc additions. A well-designed busbar trunking system also gives clearer visibility into how future loads could be supported, instead of relying purely on spare capacity assumptions inside cable trays.
How Cable-Based Power Distribution Typically Works
In a traditional arrangement, power from the main switchboard is taken to loads through copper or aluminium cables, routed via trays, ladders, and junction boxes. This form of cable-based power distribution is familiar to teams, simple to understand, and flexible at small scales. For modest loads and relatively static layouts, it continues to be a reasonable solution.
As distances and currents increase, the number of parallel runs, joints and terminations can rise quickly. That adds to the installation time and to points that need inspection over the life of the system. The complexity grows when each new rack, panel or floor demands a new routing. At the higher current levels, appreciation of heat dissipation and voltage drop becomes necessary or else the application of ‘oversized’ cable will start whittling away at how cost effective it is to continue with what has worked in the past.
What Sandwich Busbar Trunking Brings to the Table
A sandwich busbar trunking arrangement takes a different approach. Instead of multiple loose cables, it uses compact, enclosed conductors in a factory-built housing, with defined ratings and tested performance. Tap-off boxes are attached along the route to feed downstream loads as required.
Key characteristics of a modern busbar trunking system include:
Compact footprint compared to multiple cable runs with trays and supports.
Higher mechanical strength, with enclosures that are tested for short-circuit withstand.
Simplified installation, because modules are bolted together rather than each cable being pulled and terminated individually.
Easier modifications, where new tap-off points can be added without disturbing the rest of the run
These features make sandwich busbar trunking particularly suited to environments where space is at a premium and power density is high, such as data halls, process areas, or multi-storey buildings with frequent layout changes.
Practical Differences That Impact Design
When comparing cables and a busbar trunking system, it helps to look beyond the basic question of “Will it carry the current?” and examine what the installation will mean over the next decade.
Some practical differences include:
Routing and aesthetics: Overhead sandwich busbar trunking often keeps power paths cleaner than large bundles of cables in trays.
Losses and heat: The conductor arrangement and enclosure design can reduce losses, improving efficiency compared to heavily loaded cable-based power distribution.
Inspection and maintenance: Fewer exposed joints mean less routine checking, and visual inspection is often easier.
Change management: When new loads appear, adding a tap-off unit along a busbar can be quicker than pulling new cables from the board.
For many sites, the tipping point for a power distribution upgrade arrives when every new change request requires significant rework of cables, or when thermal limits and available tray space begin to constrain future plans.
Real-World Use Cases for Modern Busbar Trunking Systems
There is no single rule that says, “at this current level, you must use sandwich busbar trunking”. Instead, context matters. A few real-world examples illustrate where a busbar trunking system becomes the more sustainable option:
An existing mid-size data center that is looking to grow its rack density and add AI workloads might look at deploying overhead bus bars to distribute power throughout each row, in some cases enabling flexible movement of racks or tapping as needed without having a large shutdown.
For an existing floor in a factory adding new production lines, it can run busbars over the line to take away trays and feed distribution panels and machines from local tap-off boxes.
A commercial building retrofitting several floors of office and IT space could transition from legacy cable-based power distribution to busway, allowing risers to remain uncluttered and tenant changes in the future easier.
For those situations, the power distribution retrofit is less a matter of style and more about managing future disruption, downtime and rework.
Planning a Power Distribution Upgrade Without Disrupting Operations
The transition from cables to sandwich busbar trunking is best considered as a progressive engineering exercise rather than one large changeover.
Useful planning steps include:
Identifying critical feeders where an upgraded power distribution will deliver the most benefit with the least downtime.
Dividing the change into steps that can be performed during scheduled downtimes or low-traffic times.
Ensuring that power routes stay aligned with cooling, rack, and containment layouts while coordinating closely with mechanical and IT teams.
In the vast majority of new generation data centre projects, a combination of overhead busbars and integrated solutions – such as the Vertiv Smart Rack – ensures power delivery continues to reside near to the IT load, minimising cable distances and simplifying capacity planning. When a second row of Vertiv Smart Racks are added at a future date, in many cases the existing busbar system can handle new tap-offs with little to no additional disturbance.
Moving Forward with Smarter Power Distribution
Choosing between cables and sandwich busbar trunking really comes down to how much risk, flexibility, and future cost you’re comfortable with. If your current cable system still has spare capacity, simple paths, and doesn’t change much, you can usually keep it as it is. But once every new project feels tight on tray space, heat limits, or installation time, busbar trunking starts to make more sense because it supports cleaner expansion and more predictable performance.
As a team focused on critical power and data centre infrastructure, we at Meghjit Power Solutions work with organisations to assess when cables are still the right answer and when busbars will unlock safer, more scalable designs.
Drawing on our experience with integrated solutions, including platforms such as Vertiv Smart Rack, we help customers implement upgrades in stages that match their budgets and risk appetite. We are also proud to share that we have been recognised by Vertiv as their “Emerging 1 Phase Contribution Partner” for 2024 among more than 140 partners across India, and we bring that commitment to every project we undertake at Meghjit Power Solutions.
Some FAQs
Q1. Is sandwich busbar trunking always better than cables?
No, not in every case. Traditional cabling still works well when loads are modest, the layout is simple, and you don’t expect many changes. Sandwich busbar trunking really starts to pay off when currents are higher, circuits are more complex, or you’re frequently reshuffling loads, because its organised design and easier upgrades can justify the extra spend.
Q2. Is it possible to convert part of an installation from cables to busbar?
Yes. A power distribution retrofit is not an all-or-nothing proposition. Typically, many multi-use or complex buildings start by replacing only the critical or heavily loaded feeders with sandwich busbar trunking, while secondary circuits remain wired in cables. Additional sections can be shifted to busbar over time, whenever budgets and planned shutdowns allow, which helps lower risk and spread the cost more evenly.
Q3. Where is busbar trunking most commonly used in practice?
Sandwich busbar trunking is most often seen in data centres, industrial facilities, commercial buildings, and large campuses or infrastructure projects where power demand is high and the layout is likely to change in the future.
