What is a Bus Bar?
A bus bar is a conductive component, typically made of metal, that collects electrical power in one location and redistributes it to multiple circuits or devices. Bus bars are essential for both electrical grounding and power distribution within a system. They come in various shapes and configurations — such as flat strips, solid bars, or hollow tubes — depending on the system’s current requirements and spatial limi
Why we use bus bar
Bus bars offer a more efficient and cost-effective alternative to traditional cabling systems. Streamlining installation, reducing material costs, and minimizing maintenance over the life of a system. Because bus bars eliminate wire routing errors and simplify upgrades or reconfigurations, they reduce downtime and make system modifications faster and less disruptive to operations.
From a performance standpoint, bus bars also improve electrical efficiency by minimizing voltage drop and optimizing spacing to reduce inductance and resistance — both key factors in stable power distribution.
Materials
Metals such as silver, copper, gold, and aluminum are all highly conductive, but copper and aluminum are the most commonly used across industries due to their favorable balance of performance, weight, and cost. Because excellent electrical conductors are also efficient thermal conductors, these metals are ideal for both electrical and heat management applications.
Copper and aluminum are available in many forms — including sheet, foil, bar, rod, and tube — and in a range of alloys that modify their physical characteristics. Alloying can enhance properties such as tensile strength, hardness, or machinability, though these improvements often introduce trade-offs. For example, increasing machinability may reduce conductivity, or achieving a smaller footprint may require a heavier bussing system.
Selecting the right metal or alloy depends on the system’s specific mechanical and electrical requirements, as well as cost considerations. A clear understanding of these material properties ensures that the optimal balance between performance, durability, and efficiency is achieved.
The conductivity of pure aluminum is roughly 61% of copper, but it is less than 1/3 the weight of copper. This makes it roughly twice as conductive per pound as compared to copper making it an excellent substitute where there is a weight limitation. Like copper, the various aluminum alloys come in different tempers and have differences in their properties making selection dependent on mechanical/structural/electrical needs.
Copper Temper
The temper of a metal refers to its hardness, which for copper and its alloys is obtained by annealing or cold finishing after the annealing process. Unlike steel and aluminum, copper and copper alloys are not strengthened by heat treating in the final stages of processing. During annealing, air is excluded by flooding the furnaces with protective atmospheres controlled to prevent scaling, staining, or the penetration of the metal by oxygen or hydrogen. Cold finishing is defined as the permanent deformation or strain produced in the metal by external forces that are applied while the metal’s temperature is below its recrystallization point. It can be achieved by rolling, bending, stretching, or hammering the metal while it is cold.
To a large degree, the hardness of the metal determines the application. Due to the end use of the product, copper bar is generally available only in the harder tempers and copper sheet in softer tempers. This has to do with how the two different forms of the metal are most commonly used. The two extremes of temper are denoted as "hard" and "soft". The Copper Development Association has installed a numbering convention H01 (soft) to H04 (hard).
Copper Rod and Bar
Annealed Metal (Soft) - Recrystallized Grains - Produced by Annealing Hard Metal - Special Soft Tempers are used for short radius bending, cold heading and cold swaging. Cold worked surfaces are suitable for most polishing.
1/2 Hard Metal (Cold Worked) - Distorted and Broken-up Grains - Produced by Cold Drawing or Cold Rolling Soft Metal to Finish Size. Common Hard Temper Rectangular and Square Bar. Standard Bus Bar Temper. Used for parts requiring machining, large radius bends, slight cold heading and slight cold swaging.
Full Hard Temper (Cold Worked) - Much Distorted and Broken-up Grains - Produced by Cold Drawing or Cold Rolling Soft Metal to Finish Size. Common Hard Temper for Round Rods. Used for parts requiring machining. Generally, not suitable for bending, cold heading and cold swaging. Hard tempers are favorable to blanking, shearing and machining.
Sheet, Strip, and Roll Copper
Cold Rolled Annealed Temper (Soft Metal) - Recrystallized Grains - Produced by Annealing Hard Metal - Standard Soft Roll Copper is commonly used for deep drawing and spinning. The surface on drawn parts is suitable for most polishing requirements.
Soft Temper Annealed Metal (Soft Metal) - Recrystallized Grains - Produced by Annealing Hard Metal - Commonly used by sheet metal craftsmen. Used for moderate drawing and cupping. The surface on drawn parts is suitable for most polishing requirements.
1/4 Hard Metal (Cold Worked) - Distorted and Broken-up Grains - Produced by Cold Rolling Soft Metal to the Finish Thickness. Special Hard Temper suitable for shallow forming.
1/2 Hard Metal (Cold Worked) - Distorted and Broken-up Grains - Produced by Cold Rolling Soft Metal to the Finish Thickness. Special Hard Temper suitable for 90 deg. bends.
3/4 Hard Metal (Cold Worked) - Much Distorted and Broken-up grains - Produced by cold Rolling Soft Metal to the Finish Thickness. Suitable for 90 deg. bends. Favorable to blanking, shearing and machining.
Flexible Bus Bar
Flexible bus bar are several thin layers of a conductive metal that are laminated together to mitigate against the effects of mechanical vibrations, thermal expansion, and alignment issues with connections. Flexible bus bar carries more current per cross sectional area while increasing the dissipation of heat to maintain a cooler system (when compared to solid bus). The insulation jacketing used on flexible bus bar is typically a self-extinguishing PVC and electrically resistant. The ends are welded together to make a solid connection point eliminating the need for lugs, improving electrical conductivity, while maintaining flexibility throughout the entire bar to ease installation.
Epoxy Coated Bus Bar
Epoxy coating bus bar is the perfect insulation for conductors that are oddly shaped, have unique sizes, or those which may be known to undergo stress during installation. Unlike most other types of insulation, the epoxy powder is applied after all required bending, contouring, punching and milling is complete. In doing so, the insulation will be consistent throughout the entire conductor run.