BS EN 61238-1 is the standard that covers compression and mechanical connnectors for power cables at rated voltages of up to 36kV. There are two classes defined within the standard - Class A which includes short circuit testing and Class B which does not include this testing. Crimp testing and lug testing sees three samples subjected to tensile testing, The samples must be 40x the cross-sectional area in mm2 for aluminium conductors, and 60x the cross-sectional area in mm2 for copper conductors (in N) up to a maximum of 20,000N. A further six samples are the subjected to tests in the following sequence: For both Class A and Class B tests on crimps and lugs, the variations in resistance are analysed statistically.
Class A Initial resistance measurements Heat cycling to raise the reference conductor to 120oC Resistance measurements after 200 cycles, before short circuit Short circuit at 25kA raising the conductor to between 250oC to 270oC Resistance measurements after 200 cycles after short circuit Resistance measurements every 75 cycles up to a total of 1000 cycles Class B Initial resistance measurements Heat cycling to raise the reference conductor to 120oC Resistance measurements after 250 cycles Resistance measurements every 75 cycles up to a total of 1000 cycles