To understand the weight of the , one must first appreciate the authority behind it. Indian Aluminium Company (Indal) was a pioneer in the Indian aluminium industry, and its merger with Hindalco created one of the world’s largest integrated aluminium producers.
A unique aspect of the Indal Handbook is its engineering section on AC losses . For busbars wider than 100mm, the current density shifts to the edges. Indal recommends using (e.g., two 50x10 bars instead of one 100x10 bar) to maximize surface area and minimize skin effect losses.
The handbook dedicates significant space to dimensional and electrical data. Here is the synthesized version.
| Parameter | Indal Spec | Equivalent Standard | | :--- | :--- | :--- | | Material Grade | 6101 T6 | EN 755, ASTM B236 | | Conductivity | 59.5% IACS min | IEC 60152 | | Tensile Strength | 170-200 MPa | IS 5082 | | Electrical Resistance | 0.0279 μΩ·m | IEC 60947-1 | Indal Handbook For Aluminium Busbar
Procedures for calculating the mechanical forces and temperature rise during a fault event to ensure the busbar supports do not fail.
Aluminium expands twice as much as copper per degree Celsius. Most engineers see this as a flaw. The INDAL handbook sees an opportunity.
Every electrical engineering library should digitize the INDAL Handbook. Its physics don't age. To understand the weight of the , one
By following the Indal guidelines (proper jointing, Belleville washers, anti-oxidant compound, and thermal expansion management), engineers achieve systems that are as copper.
Because aluminium has a lower specific heat compared to copper, its temperature rises faster during a short circuit. However, the handbook details how to calculate the necessary cross-section to limit this temperature rise, ensuring the busbar survives the fault duration until the breaker trips. It also details the mechanical support structures required to withstand the immense magnetic forces generated during a short circuit—forces that can rip inadequately supported bars from their insulators.
| Busbar Size (mm) | Weight (kg/m) | DC Resistance (μΩ/m) | Ampacity (AC, 50Hz, 40°C Rise) | | :--- | :--- | :--- | :--- | | 25 x 5 | 0.34 | 25.3 | 165 A | | 40 x 6 | 0.65 | 13.2 | 300 A | | 50 x 10 | 1.36 | 6.3 | 550 A | | 100 x 10 | 2.70 | 3.1 | 1100 A | | 120 x 12 | 3.88 | 2.2 | 1500 A | For busbars wider than 100mm, the current density
Indal supplies "Indal Silver" (clear anodized) or "Indal Gold" (colored anodized) busbars.
: Essential techniques for ensuring low-resistance joints, often the most vulnerable point in an aluminum system. Technical Sizing and Calculations