High voltage load switch completely using the vacuum switch arc advantages and corresponding operating mechanism, due to the high voltage load switch does not have the ability to interrupt short circuit current, so it is simple in structure, suitable for small current, the frequent movement of the occasion, the common indoor high voltage load switch and outdoor column type two.
Many kinds of high-voltage load switch, the structure can be divided into oil pressure vacuum load switch, high voltage load switch, six sulfur hexafluoride gas type high voltage load switch, high voltage load switch and pressure type high voltage load switch; to operate for manual operation of the high voltage load switch and electric high voltage load switch two, these products are concentrated used in the distribution network, such as the ring network cabinet, the more popular is the high-voltage vacuum load switch, high voltage load switch with fuse devices such as China's reform of city network to promote the work of more and more attention, and the basic principle and structure characteristics of high voltage load switch described below two typical.
The high voltage load switch is installed on the fixed bracket. Operating mechanism which should be in accordance with the provisions of the operation, especially, if the actuator is electric or pneumatic, its operation should be carried out in the lowest voltage or the minimum pressure, unless the current truncation will affect the test results. In the latter case, the voltage or the pressure of the load switching operation should be selected within the specified range, so that the maximum speed and maximum arc extinguishing performance can be made when the contact is separated. In the above conditions, the load switch can be operated satisfactorily when the load is switched on. If possible, data should be recorded such as moving contact. Non human operation of the load switch, you can use a remote control device to operate.
1.The choice charged side connection, due consideration should be given when the load switch is connected with a power supply from both sides can be arranged, and the actual load switch side is different from the other side of the layout, power supply test circuit shall be attached to the side of the load switch can reflect the most heavy work conditions. If there is any doubt, a part of the operation should be carried out at one side of the load switch, and the other part of the operation should be carried out on the other side of the load switch.
2 the closing and opening test of a three pole high-voltage load switch operating at the same time, except as otherwise provided, shall be carried out according to three-phase.
The closing and opening test of the pole pole switch (composed of three single pole high-voltage load switches), except for the capacitive load with special requirements, the single phase is carried out.
3.In addition to filled with liquid or gas load switch and vacuum load switch, if there is a significant flame or metal particle powder splash, nearby test may require the metal screen on the live parts and leave a prescribed by the manufacturer and their security clearance. The metal shield, the bracket and other normal grounding parts shall be insulated and connected with each other and connected to a suitable grounding device to indicate whether there is any obvious leakage current to the ground.