The mechanical and electrical type tests were successfully performed according to overhead line standard EN 50341-2-4 (wind and ice zone 2) on full-scale crossarms.
For the mechanical type test, the exceptional load case of unbalanced ice loads (load case J) was tested under realistic conditions. The forces were applied via ropes at four application points. Strain gauges as well as angle of rotation and displacement sensors were used to record the strains and deformations of the crossarm. Four load levels ranging from 0.5 to 2.3 times the maximum operating load were tested.
The electrical type test included a wet switching impulse as well as a lightning impulse test between the individual phases and between the phases and the grounded ends of the crossarm. A 400 kV rating was successfully achieved for all test distances. The corona inception voltages were above the required voltages.
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