Overflow is through electricity protection. Three-part electrical current protection refers to a mechanism for the protection of electrical current speeds (para. 1), time-limited electrical current speeds (para. 2), time-bound overtow protection (para. 3), which combines with a mechanism for the protection of excess currents。
(b) in the first segment, a one-second jump in the peri-zone is generally protected at a distance from the main line
(b) paragraph 2, with a time limit of approximately 0. 3 to 0. 5 seconds to jump, generally to protect the entire circuit and possibly with a small extension
In paragraph 3, the delayed jump with n-seconds is generally fixed on the basis of avoidance of maximum load currents, and the entire protected line includes a significant portion of the lower level, depending on the circumstances。
Short-circuit currents are generated by faulty lines, equipment, etc. In the power supply system. Short-circuit currents are much larger than when the lines work normally, and this need not be explained too much. This current value and the duration of the current value are measured by means of an electric current sensor, which is the basic principle of current protection when the current value is complete。
The closer the faulty current to the power point, the greater the short-circuit current。
Passive protection, also commonly referred to as fast-track protection. This protected current fixation value is very large and has no timing. In other words, as long as this current value is reached, the protective device must move immediately (real reaction speed at millisecond level). However, in order to guarantee protection selectivity (the failure of the lower line does not enable the upper level of protection action), fast-breaking protection does not protect the entire length of the line. So, don't look at it as a part of it. Break-up protection is not the main protection of the line
Overture protection. The protected current fixation value is smaller than a period, and there is a time for consolidation. The action is protected after the circuit current has reached fixed values and lasted for some time. The current fixation value of the excess 2 segment must be guaranteed to protect the entire length of the line and be extended to the first half of the lower line. The second segment is the primary protection of the line and serves as a remote backup for the lower-level line。
Overture protection. The protected current fixation values are smaller than the two segments and take longer than the two. The three-part protections will not only ensure the full length of the line, but will also ensure a longer protection than the second-level excess. Three segments of protection are the back-up protection of the line and serve as the back-up protection of the lower (or even lower) line。
