Requirements for the distance between the knife switch and the static contacts during and after the closing of the knife switch
Thread Content
Requirements for the distance between the knife switch and the static contacts during and after the closing of the knife switch
Are there any distance requirements in this regard? Especially after closing, the moving and stationary contacts are in perfect contact; there is no distance at all
The question you’ve asked is actually just one: it involves the process of moving from a safe distance to no gap during closing. Generally, during opening, the distance is such that it exceeds the safe distance corresponding to the rated voltage. The closing process is rapid. If you’re referring to circuit breakers, for 6KV and 10KV systems, this distance is usually 11 MM; it is zero during closing
The cool moderator is referring to the switch (circuit breaker). The original poster is asking about circuit breakers. The opening and closing of the knife switch are both relatively slow. The minimum clear distance required to ensure isolation between the static and moving contacts of a disconnect switch, when the switch is in the open position, depends on the voltage level of the switch!
The distance between the knife switch and the static contact should be greater than the static distance at which air breaks down under the worst-case conditions for that voltage level.