What kind of adhesive should be used for busbar joints

For busbar joints, the recommended adhesive is typically a hot-melt or electrical joint compound, often combined with heat-shrinkable insulating tape for moisture and electrical protection.

Electrical Joint Compounds

For high-current busbar connections, silver-plated surfaces or clean copper/aluminum contacts are often used to minimize contact resistance. To enhance joint reliability, electrical joint compounds such as Burndy's PENE8 or Penetrox A/A-13 are applied between the busbar surfaces. These compounds:

• Reduce contact resistance and prevent oxidation or corrosion.
• Are suitable for both copper and aluminum busbars, with aluminum requiring careful cleaning before application.
• Can be petroleum-based or synthetic, depending on environmental and application constraints .

Regular maintenance, including cleaning and reapplication of the compound, is recommended to ensure long-term performance, especially in corrosive atmospheres .

Heat-Shrinkable Insulating Tapes

To provide mechanical stability and insulation, heat-shrinkable busbar tapes with an inner hot-melt adhesive layer are commonly used. Examples include:

• REPL RTBM tape: Combines a heat-shrinkable outer layer with a hot-melt adhesive inner layer for moisture-tight sealing .
• Medium Voltage (MV) busbar tapes: Adhesive-coated, heat-shrinkable tapes suitable for voltages up to 24 kV, fusing layers together without sticking to the metallic busbar .

These tapes are particularly useful where busbar tubing cannot be applied or for complex geometries, providing both electrical insulation and environmental protection.

Best Practices

• Surface preparation: Clean busbar surfaces with fine emery or equivalent, and optionally silver-plate for copper joints to reduce resistance .
• Mechanical fastening: Bolted or clamped joints are recommended to maintain compression and ensure low-resistance contact .
• Adhesive application: Apply a thin, uniform layer of electrical joint compound before assembly. For aluminum, use compounds specifically designed for aluminum to prevent galvanic corrosion .
• Insulation: After jointing, wrap with heat-shrinkable tape to provide moisture and electrical insulation .

By combining mechanical fastening, electrical joint compounds, and heat-shrinkable adhesive tapes, busbar joints achieve optimal electrical performance, mechanical strength, and long-term reliability.