Main technical data rated voltage 12kV rated current 250/400/630A rated frequency 50Hz rated short-time power frequency withstand voltage 42kV rated lightring impulse withstand voltage 75kV rated making current 2.5/4.0/6.3KA rated breaking current ,max 2.0/3.2/5.0kA rated breaking current ,min 50/80/125 kA rated making current ,limit 2.5/4.0/6.3 kA rated short-time withstand current 2.5/4.0/6.3 kA rated duration of short-circuit 4s mechanical life 300000times Electricity life AC-3 250000 times Electricity life AC-4 100000 times Rated contact stroke 6±1mm Contact closing force due to bellows and atmosphere 70±30N counterforce at rated contact stroke 110±40N circuit resistance at rated contact atmosphere force ≤150μΩ shelf life 20years contact erosion limit 3mm weight of moving parts ≤0.6kg mechanical data required for matched vacuum interrupter added contact stroke 110±40N average opening speed 0.6±0.2m/s average closing speed 0.3±0.1m/s contact bouncing duration at closing operation ≤2ms contact bouncing bank amplitude of opening operation ≤2mm three-pole simultaneity ≤1ms