This element is of proper shape and cross-section to carry rated current continuously and to melt in accordance with a specific time-currentcharacteristic on heavy overload or short circuit.
The general inverse timecharacteristic is introduced, and the setting principles of current and time when inverse time characteristic is scarce or voltage transformer breaks are provided.
介绍了普通反时限特性，并提供了缺乏反时限特性段或电压互感器断线时的电流、时间整定原则。
3
At the time of failure, no matter what kind of start state of voltage phase, the zero-sequence transient current has the characteristic of inverse phase.