Mitsubishi Electric Busbar Trunking Systems Guide

What is Mitsubishi Electric busbar trunking?

Mitsubishi Electric busbar trunking consists of prefabricated copper or aluminum conductor bars enclosed in a protective housing that distributes power to multiple tap-off points. It offers an alternative to traditional cabling for commercial and industrial applications up to 6000A. Benefits include:

• Compact, high current capacity distribution
• Adjustable length segments
• Integrates with switchgear and panelboards
• Overhead, wall-mounting, and plug-in options
• Simplified installation
• Easy relocation of tap-off points

Mitsubishi Electric is a global leader in busbar technology and manufactures robust systems that provide modular, flexible power distribution suitable for a wide variety of facilities.

How does a Mitsubishi busbar system work?

A Mitsubishi Electric busbar distribution system operates by:

• Feeding high capacity incoming power into the busbar trunking from a main distribution panel.
• Distributing electricity through the length of the busbar via internal copper or aluminum conductor bars.
• Providing multiple access points to tap power off using tap boxes.
• Protecting the conductors within a sturdy enclosed housing.
• Allowing quick plug-in connections at tap-off points to supply power to equipment.
• Offering compact, impedance-optimized power distribution compared to individual cables and wires.

Busbar simplifies delivering power directly from distribution gear through manufacturing areas or structures to point-of-use loads.

What are the benefits of busbar power distribution?

Compared to traditional cabling, key advantages of busbar power distribution include:

• Less voltage drop due to lower impedance conductors
• Compact, integrated distribution pathways
• Simplified installation without pulling wires
• Adjustable tap-off locations
• High current capacity up to 6000A
• Plug-in connections accelerate modifications
• Organized, aesthetic appearances
• Cost savings in large distribution projects
• Reduced maintenance versus masses of cables

Busbar provides flexible, high capacity power delivery suitable for modern commercial and industrial applications.

What types of busbar systems does Mitsubishi offer?

Mitsubishi Electric manufactures three major types of busbar power distribution systems:

Plug-In Busbar – Features plug-in tap-off boxes to simplify connections at multiple points along busbar lengths.

Wall-Mounted Busbar – Feeds power horizontally along walls to integrate with wall-mounted distribution equipment.

Overhead Busbar – Distributes power from overhead, hanging down to connect equipment. Frees up floor space.

All types utilize conductor bars protected within enclosed housings and offer similar capacities and options. The system can be tailored to facility layout and distribution requirements.

How much current can Mitsubishi busbar handle?

Mitsubishi Electric busbar trunking offers ampacities starting from 100A for branch circuits up to 6000A for main feeder applications.

Some maximum capacities per voltage include:

• 6000A at 415V with high purity copper busbar
• 5000A at 440V with 99.9% IACS copper
• 3200A at 600V using aluminum busbar

The number of internal conductor bars and their cross-sectional area determines the maximum current ratings. Copper busbar allows the highest capacities. Mitsubishi Electric offers among the largest busbar ratings globally.

Can you tap power from a Mitsubishi busbar?

Yes, one of the key advantages of busbar distribution is the ability to easily tap power off the busbar system using:

• Plug-in tap-off boxes – Allow quick connections by plugging into receptacles along the busbar length.
• Fixed tap-off boxes – Provide dedicated ports to hardwire loads directly to the busbar.
• Circuit breaker tap-offs – Integrate miniature circuit breakers or fuses for tap-off points.

Tap boxes are available from 30A to 400A ratings depending on the design. Multiple taps can be distributed along a single busbar run to supply power where needed.

How do you install Mitsubishi Electric busbar?

Mitsubishi Electric busbar installation involves:

• Planning layouts to optimize lengths and locate tap-off boxes conveniently.
• Hanging overhead systems using factory hangers. Wall-mounting at 8-14 feet high.
• Landing and connecting appropriately sized feeder cables.
• Connecting to main distribution equipment like switchgear.
• Anchoring securely to walls/ceilings to support weight.
• Grounding the housing properly according to codes.
• Keeping busbars straight, level, and aligned without bending.
• Testing insulation resistance and continuity prior to energization.

Careful installation according to Mitsubishi’s specifications maximizes safety, lifespan, and electrical performance.

What enclosures are used for Mitsubishi busbar?

Mitsubishi Electric busbar comes in enclosed housings designed for different environments:

Indoor

• Vented NEMA 1 metal enclosures for dry, cleaner environments.
• Rating up to IP54 for dust ingress protection suitable for industrial areas.

Outdoor

• NEMA 3R rated enclosures for wet or rain conditions. With UV, corrosion resistance.
• Hybrid indoor/outdoor ratings.

Specialized

-NEMA 4 watertight stainless steel enclosures for harsh environments.

• NEMA 4X for coastal or caustic conditions.
• Increased ingress ratings like IP65 for dusty and washdown conditions.

Proper enclosure selection matches the anticipated operating conditions while allowing heat dissipation for current ratings.

How are busbars integrated with switchgear?

Mitsubishi Electric busbar systems connect with switchgear via:

• Main incoming feeders landing conductors from main LV switchgear breakers.
• Busbar feeders connecting the system to integrated branch circuit panelboard distributions.
• Providing a common bus for distributing power from the gear room throughout the building.
• Allowing switchgear breakers to protect and disconnect downstream busbar circuits.
• Offering a prefabricated bus alternative versus extensive cabling from the switchgear.

Close integration of busbar with coordinating Mitsubishi Electric switchboards and LV power distribution equipment simplifies power flow architecture.

Is Mitsubishi busbar UL listed?

Yes, Mitsubishi Electric busbar trunking systems carry UL 857 listing and labeling. The UL 857 standard covers busbar construction, thermal testing, electrical spacing, and performance.

UL listing certifies that samples of Mitsubishi Electric busbar have passed standardized safety tests by an accredited laboratory. This includes short circuit, dielectric voltage withstand, and temperature rise evaluations. The UL mark demonstrates safety and reliability.

What maintenance is required for busbar systems?

Minimal maintenance is required for Mitsubishi Electric busbar beyond:

• Annual inspections – Check for damage, overheating signs, debris buildup.
• Connection integrity – Scan joints and terminations under thermal imaging for hot spots while energized indicating looseness.
• Contact resistance testing – Use a microohmmeter to measure across joints. High resistance denotes issues.
• Cleaning – Vacuum or wipe dust and dirt from housing exteriors and interiors with care.
• Ingress seals – Verify gaskets and seals prevent water and contaminant entry as applicable.

Following manufacturer instructions for periodic inspection and testing helps sustain peak system performance over decades of service.

How long do busbar systems last?

Properly installed and maintained Mitsubishi Electric busbar distribution systems provide extremely long service lifetimes of 30-50 years or more.

Key factors in maximizing lifespan include:

• Selecting copper or copper-plated busbars for optimal conductivity and reduced corrosion.
• Maintaining an even, clean busbar alignment without bending or distortion.
• Using adequately sized feeders to limit temperature rise during peak loading.
• Ensuring terminations and joints remain tightly torqued over years of thermal cycling.
• Avoiding exposure to damaging moisture, chemicals or fluids.
• Routine inspections to catch and address minor deficiencies before they become major.

With sturdy construction and appropriate maintenance, Mitsubishi busbar systems serve facilities reliably for many decades.

How much does Mitsubishi busbar cost?

Mitsubishi Electric busbar trunking costs around:

• $70-$100 per foot for 400A copper plug-in busbar
• $90-$140 per foot for 800A aluminum wall-mounted feeder busbar
• $250-$400 per foot installed for 4000A overhead distribution busbar

Costs vary based on current rating, mounting type, run length, accessories, and installation requirements.

Large installations can realize savings over traditional wiring and installation labor. Contact Mitsubishi Electric for an exact quote tailored to your specific project power needs and layout.

What are the alternatives to busbar distribution?

Alternatives to busbar electrical distribution include:

Conduit and Wiring

• Requires pulling multiple conductors through conduit runs – labor intensive.
• Tap offs involve junction boxes and splices.
• Changes mean rewiring – inflexible.

Cable Bus

• Enclosed insulated cables often mounted overhead.
• Limited ratings and tap-off capabilities.

Busduct

• Enclosed ducts housing conductors like busbar.
• Generally higher impedance than busbar.

When capacity exceeds 200A or flexibility is needed, busbar offers advantages over these traditional wiring methods.

How is busbar different from busduct?

Busbar and busduct both deliver power via enclosed conductive bars. Differences include:

Busbar

• Lower impedance for a given ampacity.
• Flat bare or insulated copper or aluminum bars.
• Slimmer, simpler construction.
• Air alone often provides insulation.

Busduct

• Encloses bundled insulated cables rather than solid bars.
• Bulkier duct-like construction.
• Insulation required between current carrying elements.
• Mostly used for feeder runs versus low voltage distribution.

Busbar offers more streamlined, optimized power delivery for branch circuit distribution applications within facilities.

How do you size a Mitsubishi busbar system?

Properly sizing a Mitsubishi Electric busbar system involves:

• Summing the ampacity demands of all expected loads. Consider future growth.
• Choosing the minimum busbar amp rating that meets or exceeds the total current.
• Limiting the allowable temperature rise based on the enclosure and operating environment.
• Calculating voltage drop based on run lengths and conductor resistivity.
• Selecting any integrated components like breaker panelboards to match ratings.
• Right-sizing the number and ratio of tap-off boxes to distribute power properly.