Electrotechnical bars

An electrical busbar is a current-carrying element in the form of a flat strip, designed to distribute electric current within a system. Depending on the operating conditions, busbars made of copper or aluminum are used. The main difference between aluminum and copper electrical busbars is that to carry the same current load, aluminum requires a larger cross-sectional area. However, aluminum is lighter than copper, corrosion-resistant, less expensive, and provides sufficient conductivity for most applications. That is why aluminum holds a special place among all materials used in the production of electrical busbars.

What is the purpose of an aluminum busbar?

An aluminum busbar is used as the primary conductive element for distributing load between parts of equipment. It ensures stable operation at high currents, allows direct connection of equipment without intermediate connectors, and, thanks to its open profile, effectively dissipates heat.

The shape, cross-section, and alloy type are selected based on current strength, cooling conditions, operating mode, and installation requirements. In practice, this allows precise calculation of busbar parameters for specific technical tasks without excessive cross-sectional margins.

Manufactured by extrusion or rolling, aluminum busbars are easily adapted to specific technological tasks and are used in various fields, from medicine to aviation:

• Medical industry: equipment and instruments;
• Aircraft manufacturing: airframe components and parts;
• Construction: frames and architectural elements;
• Commercial transport: frames of railcars and containers;
• Consumer goods: cookware, furniture, appliances;
• Electrical engineering: capacitors, radars, antennas, etc.

Nevertheless, the widest application of aluminum busbars is found in the electrical engineering sector: in high and low voltage devices, distribution panels, main power lines, and industrial equipment.

What types of aluminum busbars exist?

In industry, rectangular cross-section busbars are most commonly used, but flat, bent, and specially formed variants also exist. The most common profiles have thicknesses ranging from 3 to 10 mm and widths up to 120 mm. The type and shape of the busbar are directly related to its ability to withstand a certain current load and provide the required current-carrying capacity, especially under intensive operating conditions.

How many amperes can an aluminum busbar carry?

The current-carrying capacity of a busbar directly depends on its cross-section, material, and operating conditions. Calculations consider not only the profile dimensions but also temperature conditions, installation method, and ventilation availability. Under natural cooling conditions (without forced air or liquid cooling), standard reference values are used.

Below is an approximate table showing the permissible continuous current of aluminum busbars during prolonged operation. These values serve as a baseline for selecting the appropriate cross-section for a given load.

.

These values serve as guidelines for designing busbar systems, but calculations should be refined according to specific operating conditions. If necessary, the cross-section is selected with a heating margin or active cooling is used.

“Alupro” offers electrical busbars without coating in the following sizes: width from 40 mm to 140 mm, height from 4 mm to 23 mm. Products can be made from soft alloy (AD0) or hard alloy (AD31). All aluminum electrical busbars are manufactured to order starting from 300 kg. Delivery time is from 5 working days.

If you are unsure which busbars to select, our sales and engineering specialists are always ready to help you choose the right products and solutions according to your requirements.