Why Is The Contact Resistance Of The Parallel Groove Clamp Significantly Lower?

The single bolt parallel groove connector adopts a groove-shaped structure, which creates a large-area geometric fit interface between the wire and the clamp. Compared to simple point contact, a larger contact area corresponds to a larger current transmission cross-sectional area. According to Ohm's law, resistance is inversely proportional to the cross-sectional area; therefore, the wider the contact area, the lower the overall resistance.

In the actual assembly process of parallel groove clamp, radial pressure is applied to the wire by tightening the bolts, causing micro-plastic deformation of the metal surface. This micro-pressurization increases the number of contact points between peaks and valleys on the conductor surface, reducing the inter-peak gap and thus increasing the actual contact area. The increased actual contact area directly reduces the interface resistance at the electronic conduction level.

The materials used in parallel groove connector are highly conductive metals such as aluminum alloys or copper alloys, which have low resistance characteristics. Good material conductivity combined with a tight contact structure reduces energy loss at the contact interface, making the current path smoother and resulting in superior overall resistance performance.