GRL Low-Voltage Enclosed Busbar Systems

Modern power distribution increasingly relies on modular busbar systems for efficient and safe electrical wiring. A  low-voltage Enclosed busbar system uses conductive bars (instead of individual cables) to deliver power to devices within switchgear and control cabinets.

GRL’s Low-Voltage Enclosed Busbar System exemplifies these benefits: It eliminates drilling and cuts installation time and cabinet space by up to 60%. Key advantages—such as faster setup, easy reconfiguration, and high fault ratings—make busbar systems ideal for smart power distribution. As renewable energy and smart grids expand, integrated busbar solutions are fundamental to future power distribution.

Types of Busbar Systems

Busbar systems vary by configuration, form factor, and application. Understanding the electrical busbar types available helps select the right solution:

By Structure: Busbars may be open or fully enclosed. Enclosed busbar systems house all phases in an insulated channel, improving safety and meeting international standards. Enclosure ratings can reach IP60, keeping conductors protected.

By Size and Rating: Standard sizes include 30 mm, 40 mm, 60 mm, 100 mm, and 185 mm systems. For example, a 60 mm busbar system typically carries 800–2500 A. GRL’s range covers 60 mm and larger busbars rated up to 4500 A for heavy industrial power distribution.

Busbar Trunking: In many installations, busbar trunking (rigid enclosed busbar conductors) efficiently carries high current over long runs. GRL’s busbar trunking uses aluminum and reinforced polymers to support 400–4500 A at voltages up to 1000 VAC or 1500 VDC. Trunking is common in factories, data centers, malls, and transit systems.

Compact vs. Wide-Row Busbar system: A compact busbar design packs phases closely together in the enclosure, minimizing footprint. A wide-row busbar spaces the conductors farther apart, often used where higher voltage clearance or specialized connectors are required.

Plug-in and Terminal Busbars: Plug-in busbar systems feature adapter modules (such as circuit breakers or fuse switches) that plug directly onto the rail. These modular power rails allow devices to be mounted without cables. A terminal busbar is a passive section or connector block where external cables or feeders attach to the bus system.

Specialized Busbars: Some systems are designed for specific applications. For example, photovoltaic busbar configurations integrate DC fuses and isolators for solar arrays. Others include circuit protection busbars, which have integrated breakers or fuse holders on the rail. GRL offers PV-rated fuse links and boxes so that a photovoltaic busbar assembly meets NEC/IEC requirements.

Common busbar configurations by size include:

30mm Busbar System

40 mm Busbar System

60 mm Busbar System

100 mm Busbar System

185 mm Busbar System

These standardized busbar ranges cover most industrial power needs. Manufacturers like GRL also offer non-standard sizes and special busbar clamps or connectors for custom solutions.

Enclosed Busbar System Components, Accessories, and Protections

A enclosed busbar system is more than just flexible insulated copper busbars– it includes a variety of components and accessories for switching, protection, and customization:

Fuse Switch Disconnectors: Fuse disconnect switches and panel-mounted fuse switches plug directly onto the busbar to protect circuits. For example, GRL’s DNH-series fuse switches (vertical or horizontal) snap onto the rail and incorporate fuse holders to disconnect overloaded circuits. These eliminate traditional screw-wire fuses, speeding up installation.

Circuit Breaker Adapters: Standard MCCBs (molded-case circuit breakers) require adapters to fit busbars. GRL provides MCCB adapter kits (breaker adapters) for 630 A and 800 A 3-pole breakers. These adapters let plug-in breakers mount onto busbars, creating busbar-mounted breakers in a modular switchgear. The adapters greatly simplify installation and maintenance.

Isolator Switches: A busbar isolator switch provides a lockable break in the busbar for safe disconnection. GRL offers isolator modules that plug into the rail, allowing sections of the busbar to be safely shut off for maintenance or emergency shutdown. This meets the requirements for rapid isolation in distribution panels.

Busbar Fuse Holders: For fused protection, a fuse box for busbar (a fuse base assembly) mounts on the rail. GRL’s busbar fuse boxes hold high-voltage or NH fuses and attach directly to the busbar, enabling easy fuse replacement without rewiring.

Busbar Connectors and Clamps: Busbar connectors join lengths of busbar or transition between different conductors (e.g., copper-to-aluminum). GRL provides specialized clamps and connectors to ensure tight, low-resistance joints. Common busbar accessories include end stop blocks, phase separators, and support brackets.

Protective Covers and Insulators: Safety covers insulate exposed busbar sections or bridge unused segments. GRL’s busbar protective covers and insulator strips keep operators safe and prevent shorting when panels are open.

These components turn bare busbar bars into a full circuit protection busbar system. By integrating breakers (via MCCB adapters), fuse-disconnectors, isolators, and smart meters directly on the rails, engineers create compact, resilient distribution panels.

GRL’s comprehensive product line can offer everything needed: from 60 mm busbar systems and modular power rails to plug-in fuse-switches, MCCB adapter kits, isolators, and smart energy meter modules. We invite you to explore GRL’s offerings and learn how our integrated busbar systems and protection devices can meet your needs. Contact our technical team to discuss your project requirements and find the right solution.

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