Crimp and Lug Test
Publish Time: 2019-03-27 Origin: Site
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:
Class A |
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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 |
For both Class A and Class B tests on crimps and lugs, the variations in resistance are analysed statistically.