Track Busway Comparison STEEL and ALUMINUM Leaders USA TrackBusway & Starline *
Photos: Top image shows open-slot STEEL Track Busway installed below an acoustical tile ceiling with plug-in PowerDrops. Bottom image shows insulated copper busbars inside the open-slot channel.
Comparing Overhead Plug-In Track Busway Systems
On this page we compare the STEEL USA TrackBusway system — an open-slot, plug-in busway designed for localized branch-circuit distribution — with the leading ALUMINUM Starline * system.
This comparison highlights how the two systems differ in housing material, availability, and electrical strategy. It also explains how plug-in access is commonly managed as aluminum systems may be configured for much higher ampacity ranges (up to 1250A).
Use the blue links below and quick-access buttons to explore detailed comparisons:
KEY ADVANTAGES OF STEEL TRACK BUSWAY
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Lead Times → STEEL Track Busway has the Fastest Lead Times in the Busway Industry — standard orders within 7 to 10 working days, even as high-ampacity ALUMINUM systems have extended, data-center-driven lead times.
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Material Cost → STEEL Track Busway uses #8 AWG copper conductors rather than the larger, heavier copper bars required for high-ampacity ALUMINUM busway, helping reduce both weight and material cost.
Before diving into those differences, it helps to understand where both systems are similar.
Need help choosing the right busway system?
USA TrackBusway™️ provides complimentary drawings and system guidance to help you select and configure the right Track Busway solution.
Watch STEEL Track Busway in Action
See how STEEL track busway stacks two channels vertically to support 3-phase or multiple single-phase circuits — all on one suspended run of track busway.
Video summary: The animation shows STEEL Track Busway suspended overhead with two stacked channels. Power feeds energize the busway, and plug-in units are inserted along the run to supply 3-phase or multiple single-phase circuits.
KEY SIMILARITIES WITH ALUMINUM TRACK BUSWAY
Both STEEL and ALUMINUM track busway systems use a plug-in architecture that allows tap-off units to be positioned along a run more flexibly than conduit-and-junction-box layouts. This shared plug-in approach is what enables faster changes and easier repositioning of loads.
- Voltage Capabilities ↘ Both systems are listed to UL 857 busway standards for use up to 600V in single-phase and three-phase layouts.
- Installation ↘ Both install far faster than hand-wiring conduit-and-junction-box layouts.
KEY DIFFERENCES BETWEEN STEEL AND ALUMINUM TRACK BUSWAY
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Amperage & Branch Feeds ↘
As amperage increases, higher-ampacity busway systems often manage plug-in access using enclosed housings and closure or cover components between tap-off points,
rather than leaving continuous open access along the run.
ALUMINUM systems may be configured for high-ampacity distribution from centralized tap-box connections (up to 1250A).
STEEL Track Busway is designed for localized branch-circuit distribution, with branch circuits commonly fed from splitter enclosures positioned above the tap boxes. Within the UL 857 continuous plug-in category in the U.S. (225A or less), this architecture supports continuous open-slot access along the run. → See Amperage section + diagram
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Configurations & Layouts ↘
Both systems support single-phase and three-phase distribution. STEEL Track Busway uses double-deck lengths to deliver three-phase power,
while ALUMINUM systems provide three-phase within a single housing.
STEEL stacked housing can alternatively be used to take advantage of a unique capability: supplying up to four single-phase circuits from the same suspended footprint using (2) 2-pole line feeds — a level of single-phase flexibility not possible with a single ALUMINUM housing. → See Unique Features
UL 857 Continuous Plug-In Busway Boundary
- Continuous open-slot access is most commonly used for branch-circuit plug-in distribution.
- As ampacity increases, access is typically managed with enclosed housings and defined tap-off points.
- Higher-ampacity designs commonly use covered or windowed tap-off points instead of continuous open access.
For definitions and background terminology, see What Is a Track Busway or Why Track Busway.
ALUMINUM vs. STEEL Track Busway – Side-by-Side System Comparison
ALUMINUM busway may be configured for higher ampacity per feed, while STEEL track busway is designed for lower-amperage distributed feeds. The comparison table below summarizes how each approach impacts installation, ampacity, and future changes. Click any feature name to jump to the matching section in the detailed comparison.
Click any feature name in the table to see details. → Jump to Lead Time details | → Jump to Material details
| Feature | USA TrackBusway (Steel) | Aluminum Track Busway |
|---|---|---|
| SPEED – Lead Time & Installation ↘ |
• Standard USA TrackBusway orders ship in 7–10 working days • Custom lengths & plug-in taps: 3–4 weeks |
• Lead times vary by manufacturer and configuration • Contractor quotes frequently show months-long delivery timelines for aluminum track busway systems, as of November 2025 |
| Material & Construction ↘ |
• 12-gauge cold-rolled STEEL housing • Insulated #8 AWG copper busbars sized for 40 A per phase |
• Extruded ALUMINUM housing • Insulated copper busbars (size increases with ampacity) • Larger copper bars in high-ampacity models can make ALUMINUM busway assemblies substantially heavier overall |
| Amperage (Per Circuit) (Per Phase)↘ |
• 40 A per circuit / per phase • Single-deck single-phase: 2 × 40 A circuits • Double-deck 3-phase: 3 × 40 A circuits • Double-deck single-phase: 4 × 40 A circuits |
• Up to 1250 A per circuit / per phase |
|
Voltage & Circuiting ↘ |
• Supports 120 V, 208 V, 240 V, and 480 V layouts • 1-pole, 2-pole, and 3-pole plug-in options are available • Stacked housing (double-deck) can be used to add additional circuit |
• Supports 120 V, 208 V, 240 V, and 480 V layouts • 1-pole, 2-pole, and 3-pole plug-in options are available |
| Unique Features ↘ |
• Stackable double-deck layout • Flip-select plug-in taps • Over/under bridge runs |
• Built-in metering options • High ampacity per feed • Centralized long-run distribution |
Detailed Technical Comparison
Dive deeper into how aluminum and steel plug-in busway systems compare across construction, electrical performance, flexibility, and installation.
Material & Construction
ALUMINUM track busway systems use lightweight extruded housings and can reach extremely high ampacity ratings (400 A–1250 A). These systems are often chosen for long continuous runs that require fewer incoming feeds. However, higher-amp ALUMINUM designs rely on large copper busbars, which can significantly increase total system weight and structural demands.
- High-ampacity models (up to 1250 A) — reduce the number of homerun feeds for high-load runs.
The STEEL track busway configuration uses #8 AWG copper conductors. Rather than larger and heavier copper busbars along every foot of the run, the STEEL system is optimized around distributed loads for typical industrial and commercial applications.
The steel housing provides a robust mechanical structure for industrial environments and also supports field-stackable busway architecture — allowing two track busway channels to be mounted vertically, adding additional circuit or three-phase capability.
- Stackable double-deck architecture — supports adding additional circuit vertically, while keeping the same overhead track busway footprint.
Voltage
UL 857 Listing & Voltage Compatibility
Both ALUMINUM track busway and STEEL track busway systems are listed to UL 857 busway standards and certified for operation up to 600 V, covering 1-pole, 2-pole, and 3-pole power drops across industrial, laboratory, and manufacturing environments.
Single-Phase Support (Single-Deck)
- 1-Pole 120 V circuits for small equipment.
- 2-Pole 208 V circuits for medium-power loads or dual-phase equipment.
- 2-Pole 480 V circuits for higher-voltage machinery.
Three-Phase & Multi-Circuit Support (Double-Deck)
Adding a second STEEL track busway channel expands both circuit count and voltage capability. The lower channel supports 1-pole and 2-pole single-phase drops, while the upper channel enables full 3-pole, 3-phase power — all within the same suspended footprint.
- 4-Pole 3-Phase capability with the upper deck.
- Up to 4 single-phase circuits in stacked configurations.
- Simultaneous single-phase + three-phase power in one run.
These modular systems create a voltage-flexible electrical backbone that supports expansion and re-configuration without re-wiring.
Amperage
Typical Overhead Power Distribution
In most industrial, manufacturing, and commercial environments, overhead power drops commonly range between 20–40 amps per workstation. STEEL track busway is designed around this reality, delivering multiple 40 A circuits within a compact suspended footprint rather than carrying high ampacity continuously along every foot of the run.
The STEEL track busway configuration uses #8 AWG copper conductors sized for distributed loads, rather than the larger and heavier copper busbars typically found in aluminum systems.
Split Once, Feed Twice — Junction-Box Splitters That Reduce Homeruns
STEEL track busway standardizes on 40 amps per phase, capable of powering various types of equipment.
STEEL Track Busway can be paired with upstream dual-feed splitter enclosures to divide higher-ampacity inputs into multiple 40 A branch feeds. (Other plug-in busway systems also support splitter configurations.)
Because STEEL track busway feeds include integrated breakers, each branch is protected and remains compliant with NEC tap rules as long as the tap length stays within the permitted 25 ft. This approach provides the required capacity without the cost, weight, or structural burden of high-amp ALUMINUM busway.
Unique Features
Three Ways Track Busway Stands Out
The examples below highlight features of the STEEL track busway system that support modular layouts and additional circuiting options.
Modular Double-Deck Layout
Stack two STEEL track busway channels vertically within the same suspended footprint to increase circuit density or combine single-phase and three-phase power without adding new raceways.
On-Site Phase-Select Orientation
STEEL track busway plug-in units for 1-pole circuits can be rotated 180° to select the desired conductor on-site, simplifying load balancing and circuit reassignment.
Over/Under Intersections
Over/under bridge kits route STEEL track busway over aisles, conveyors, and walkways while maintaining continuous power, allowing floor layouts to evolve without extensive rework.
SPEED – Lead Time & Installation
Faster Than Traditional Conduit
Both ALUMINUM track busway and STEEL track busway systems install significantly faster than conduit. With pre-engineered channels and plug-in power modules, these systems reduce field labor, minimize rework, and allow future floorplan changes without cutting or replacing pipe.
This streamlined process minimizes downtime and accelerates the time it takes to energize overhead power—an important advantage for fast-paced projects.
Installers typically follow a straightforward sequence:
- Preparation: Mark hanger points aligned with structure.
- Hanger Installation: Install hangers ~10’ apart.
- Track Assembly: Join lengths mechanically, then engage electrical joiners.
- Plug-In Integration: Insert power drops, power adapters, or device mounts.
- Commissioning: Verify continuity, grounding, and alignment.
Why Contractors Choose USA TrackBusway
- Reliable U.S. manufacturing and predictable lead times
- 7–10 business day shipping on most components
- Modular architecture reduces field labor
- Stackable design supports multi-voltage overhead layouts
Supported Voltage Options
Click the red on the wiring diagram to view all supported system voltages, including 120V, 208Y, 208V 3-phase 4-wire, and 480V.
Panelboard ‘A’ may be 120/208V or 277/480V depending on building service.
Available: 208/480V
Line to Neutral Available: 120/277V
Line to Line Available: 1Ph-208V or 1Ph-480V
Available: 208/480V
