The Effect of Thermal Stresses on the Electrical Resistance of Crimped Connections

Cables headed with crimped lugs are frequently used in test laboratories in temperature rise tests carried out to validate electrical devices. The increase in the electrical resistance of the crimped connections can cause high dissipation of power and heat during these tests, impairing their outcome. This work evaluates the effect of thermal stresses on the resistance and on the dissipated power of crimped connections. This resistance was found to be more sensitive to thermal stresses than to mechanical ones analysed in a previous work. A limit of the dissipated power from crimped connections during temperature rise tests was estimated to be about 4 W corresponding to a crimp resistance of 24 mu ohm for tests made at 400 A. Respecting these limits could avoid unnecessary rejections of equipment under test.