Bolted Connectors for Stranded Aluminum Power Conductors

Sixteen different commercial bolted connectors for 50 and 240 mm stranded aluminum cable conductors have been examined in order to identify and clarify the correlations between the quality of a connector and its design characteristics, material usage, assembly procedures, bolt numbers and configurations and other relevant parameters. The quality is assessed with basis in resistance measurements after short circuit testing and during thermal cycling as specified by the IEC 61238-1 standard. The tightening torque of the bolts was measured during connector assembly, and the resulting axial compressive forces were calculated. A very strong correlation is observed between this compressive force and the connector quality; large forces give connections with low and stables resistances. The various other design parameters considered are found to have significantly less or in some cases hardly any notable influence on the electrical test results.